Dressed in black tracksuit bottoms and t-shirt, his signature Cheetah blades replaced by gleaming white trainers, he is sitting in a cafe opposite the athletes' village in Daegu, indistinguishable from any other tanned young sportsman whiling away the empty hours pre-competition.

Appearances can be deceptive. While Usain Bolt may appear on more billboards around town, it is the inclusion of multiple Paralympic gold medallist Pistorius on the start-lists that has commanded more column inches.

To some it is an inspirational tale of courage against adversity, to others a PR-driven story in which science and ethics have taken a back seat to emotion and hype.
To the man himself, it is something far less complicated: a simple desire to run as fast as he can, against the fastest there are.

"I think I've always regarded myself just as an athlete," he says. "I'm very proud to be a Paralympian, but even Paralympic athletes are athletes just like anyone else.

"I consider myself an athlete, just a 400m specialist. When I line up I'm not going to think how great it is to be here, I'll think about how hard I'll have to work to get to the end in a time I'll be happy with.

"It's not any different from any other race. It's a great honour to be here, and this is one of the top competitions that any athlete will have the pleasure of participating in their career. But I don't run to get to a point where I've decided [appearing at the Worlds] is an accomplishment."

The journey to Daegu has been a long one for the 24-year-old from Pretoria. When he first tried to compete in IAAF events he found himself excluded by a new clause added to the sport's governing body's rule 144.2, which relates to the use of "technical aids" during competition.

Clause (e) prohibited the "use of any technical device that incorporates springs, wheels or any other element that provides the user with an advantage over another athlete not using such a device."

A study carried out by Professor Peter Brüggemann at the German Sport University in Cologne had indicated that Pistorius's carbon-fibre blades enabled him to run at the same speed as able-bodied sprinters with about 25% less energy expenditure. Pistorius and his coach Ampie Louw disagreed, appealed to CAS and won.

That was three years ago. The battle since then has been against a foe familiar to all track athletes, the clock. At the last Olympics Pistorius was 0.7 seconds off the qualifying time. Even at the start of this year he appeared to be well off the pace.

If his PB in Italy was a clear 0.18 seconds inside the Worlds qualifying mark, it was also a full half a second inside his previous best. As improvements go, it was massive.

"I've noticed a difference in attitude from my fellow competitors, because I think they respect me more," says Pistorius. "I spoke to a friend the other day who's a really well known 400m athlete. He was saying I look like I've lost weight. If anything I get treated just like any of the other guys."

That PB was also just the 18th fastest time in the world this year. On that basis, Pistorius could struggle to get anywhere near Tuesday's 400m final. So, after such a struggle to be allowed even to enter, what would now constitute success?

"There are probably two parts," he says. "One would be making it through the first and second round, trying to make the semi-final, and I think that's a realistic goal.
"The other one would be to gain as much experience as I possibly can for the London Olympics next year. This is a phenomenal chance to go through the same kind of pressure and competition as next year."

Pistorius is not the first Paralympic athlete to compete in world-class able-bodied events. His compatriot Natalie du Toit swam the open-water 10k at the last Olympics, while USA's Marla Runyan, who is legally blind, finished 10th in the 1500m at the 1999 Worlds in Seville.

Ireland's Jason Smyth, the double Paralympic champion who is also visually impaired, lined up in the 100m heats here in Daegu on Saturday evening.

But amputee Du Toit competes without a prosthetic limb, Runyan and Smyth without guides. It is Pistorius's blades which take athletics into unexplored areas, those distinctive "upside-down question-marks", as he describes them, the punctuation in a debate that can get extremely heated.

South African sports scientist Ross Tucker accepts that Pistorius is an inspiration to millions. He also thinks the scientific case is closed: Pistorius's carbon-fibre blades give him a significant advantage.

"Biomechanical studies have found that he is able to accelerate his limbs at speeds that are off the biological charts," he told the BBC.

"In sprinting one of the key things is that you have to be able to move your limbs quickly, and Pistorius can do this many, many milliseconds faster than any other athlete in history - even faster than Usain Bolt in the 100m.

"There is such an impenetrable wall of PR support for Pistorius now that for a federation to take him on and say, no, you're not allowed to run, is a PR disaster. They would be accused of discriminating against him just because he's now a success.

"But every single study so far shows the same thing, which is that there is this performance advantage as a result of the energy enhancements and the reduced mass of those limbs."

Saeed Zahedi is a biomechanist who has been at the forefront of prosthetic design for the past three decades.

"Oscar has to have his stump inside a socket, and he has to compensate all the forces around his stump," he told the BBC. "Essentially the sense of fatigue that comes from the act of compensation is a lot higher in Oscar's case than for any ordinary runner."

Richard Whitehead, the Briton who holds the double-amputee world marathon record, agrees. "Wearing prosthetic limbs, you have lactic build-up in other parts of your body. When Oscar finishes he is physically exhausted - in the race when he qualified for the Worlds, he collapsed at the finish because he was so exhausted.

"Athletes, as well as people in general, are inspired by someone doing something positive - and that's what Oscar is. He's been given a gift to participate at the highest level, he wants to push the barriers, and he has a right. As long as he qualifies like everyone else, I don't see why he shouldn't be allowed to compete in Daegu."

Has Pistorius heard any whispers from within the athletes' village?

"No, no, nothing like that. At this level we don't look at our opposition and criticise them when we don't do well. We look at ourselves.

"If you don't run a good race, you can't point fingers and anyone else. I've got a lot of respect for the guys I participate against. They know how hard I train and how much I sacrifice for the sport.

"You'll always have one or two guys that differ, are ill-informed and like controversy. There's nothing I can do about that.

"I'm very confident. There's no way the prosthetic leg can provide any advantage."

Sitting with him in the early summer sunshine at The Oval, the surprises start early.
His preferred reading material? "Bacon Busters. It's an Australian magazine about pig-hunting.

"It's a pretty blokey magazine, but they have women in it too. There's a 'Boars and Babes' section. Women in bikinis sitting on big old pigs." He grins. "I don't know how many they sell, but they must be doing alright."

Symonds is fresh off an overnight flight from his native Queensland, the marquee signing for Surrey as they prepare for this month's Twenty20 Cup campaign. A week shy of his 35th birthday, he's looking remarkably limber for a man supposedly carrying more baggage than any other active cricketer.

"I'm in the World XI for sleeping - I could sleep anywhere, any time," he says proudly, but this is only part of the story.

Fifteen seasons have passed since Symonds first announced himself to the cricketing world by smashing a world-record 16 sixes in a total of 254 not out for Gloucestershire against Glamorgan.

You'd expect him to be growing weary. Instead, there is a fresh spring in his step, a new calmness about his character. The dreadlocks of old have gone; the enjoyment of his younger years returned.

"I'm passionate about the battle in the middle," he says. "I haven't come here for fun. The competing - that's the bit I love.

"Some days training drags on, and you think, 'Agh, I've got to drag myself out of bed for this again.' You're lying if you've never felt that as an athlete. But you get there, you get warmed up, and you find a way of enjoying it - whether it's having a joke, pulling someone's shorts down - whatever it takes."

Symonds' way of enjoying things has not always been appreciated by those in positions of authority. Forget merely messing about on boats, a la Freddie Flintoff, or tugging on a ciggie while sending salacious texts like Shane Warne.

The Symonds rap-sheet is as long as the flight from Down Under. Take your pick - suspended from the Australian team in 2005 after turning up at a one-day international still wasted from the night before; shoulder-charging a streaker at the Gabba two years later; being sent home before a series against Bangladesh after deciding to ignore a team meeting in favour of a fishing trip; making unfortunate remarks about Brendon McCullum and Matthew Hayden's wife during an infamous radio interview with comedians Roy & HG.

Symonds' precious Cricket Australia contract was eventually terminated after another mammoth drinking session saw him sent home from last summer's World Twenty20 in England. He is unlikely to ever play for his country again, cut adrift after far fewer international appearances (26 Tests, 198 ODIs) than his youthful talent once promised.

So. If the Andrew Symonds of today could go back and have a quiet word with the lean 20-year-old who blasted that record-breaking 254, what would he say?

He looks out across the checkerboard green of the Oval outfield. "I think I would have done the same thing, but I would have maybe seeked out help or talked to people when - well, done things slightly differently when my profile got bigger.

"I think that's when I found life difficult. I'm a very private person and I like my space, and I look back and I didn't deal with that as well as I could have. Being in the public limelight - some days I was good, and some days I wasn't too good at all."

What used to happen on those crazy, crazy nights? Symonds has denied claims that he was an alcoholic, insisting it was more about occasional binges ("I go out and drink hard all in one hit - too fast, too much"). But surely he must have known how much trouble he was about to cause?

"It just used to build up inside me, and then I'd go and do something silly - as a release. Because my time was always bundled up with all the cricket, and the things that go with cricket, I just didn't have the time I needed for myself.

"Mum always used to say to me, 'You're gonna blow.' I could feel it all building up inside me, and then, boom! I'd go."

He pauses and scratches his chin. "We all make mistakes, although I'm not proud of some of the mistakes I've made. But I reckoned I've mellowed right out now."

What's triggered the change - age? Remorse?

"I reckon I just don't have the same pressures on me; the same requirements to play the game - the sponsors and the media and all that stuff. It's been toned right down, so I've got time for myself, to sit down and think.

"I've learned a great deal, privately and personally and professionally over the past two years, possibly as much as I did in the five before that."

Symonds is not the only live-wire in the Surrey dressing-room; the county is also playing host to both Andre Nel and the fast bowler's alter-ego Gunther. "I guess I'm attracted to the broken souls," cricket manager Chris Adams has remarked, tongue partially in cheek, but for Symonds this sort of support is all-important.

"The other thing for me was, the art of coaching is man-management as well. There's no two blokes in the team who are the same. And they have to be managed right as well. There were a lot of things that could have been handled better off the field by different organisations, and that took its toll on me, I reckon."

In some ways Symonds is the archetypal uncomplicated Queenslander. He describes his perfect day like this: "I'd wake up on a river bank or round a camp fire with the boys, cook some breakfast, jump in the boats, go up the creeks, catch a barra (barramundi) on my first cast..."

He loves rugby league, says the State of Origin matches are his favourite sporting event and would have loved to have played for legendary coach Wayne Bennett ("although I'd be broke down - I'd be on crutches like you").

In other ways he's rather more complicated. On the surface the very definition of a larrikin, he wept openly after winning the first of his two World Cup in 2003, has settled happily in hyperactive Hyderabad during his stints with the Deccan Chargers and is about to star in a new Bollywood production called Patiala House.

His cricketing skills he attributes to Ken and Barbara Symonds, the Birmingham couple who adopted him aged three months and moved the family to Australia just over a year later. Ken, a cricket nut, used to bowl at his son for hours on end; inside the house, impromptu games would be played using ping-pong balls and Christmas baubles.

"As a kid I suppose it's the best thing for developing your hand-eye coordination. It gives you confidence, and you have fun doing it. I'm very grateful for how I was reared."

I ask Symonds what he loves most about his chosen sport. Is it pinging a six right of the middle, taking a diving catch, splattering someone's stumps?

"Nah. It's the moment of victory. Before a World Cup you might train by yourself for six weeks, train with the team for six weeks, play all your group matches, make it through the semi-finals - and the moment you win that final, it's all worth it. It's all worth it.

"That's... that's... I love that moment. Doesn't matter whether I've scored a hundred or two - that's just the best feeling."

Symonds is due to return to Birmingham a few hours later to begin filming the Bollywood movie. The producers have a very specific role for him. "I've just got to look angry," he says, and raises an eyebrow.

Titles are lost. Relegation looms. Play-off places wink suggestively and then rudely rebuff advances. Sport, the love of our lives, becomes not so much a fickle mistress as an adulterous partner with the morals of an inebriated long-distance sailor.

Trapped in this abusive relationship is the humble fan, powerless to influence the very thing that exerts so much control over our happiness.

Can anything be done to alleviate this awful tension? How best to cope with the grief of season-ending defeats, with the anguish that accompanies an inexorable slide from mid-table obscurity to near-certain relegation?

Beset by footballing fears, desperate for answers, I sought out Phillip Hodson, fellow of the British Association for Counselling and Psychotherapy.

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"As biological creatures, we need to oscillate between tension and relaxation if we are to survive and thrive," he tells me. "The problems start with tension that's never relieved. When you're anxious about an event or outcome, like the position of your football team, the tension is 24/7."

Last-gasp home defeats to Bristol City should never lead to sleepless nights for anyone but the players involved, but such is the lot of the loyal supporter.

"You can't control the external event, but you can control your reaction to it," advises Hodson. "One of the easiest ways of doing that is to take some fairly vigorous physical exercise. That will make you tired, change your breathing, make you hot and then cool down, and that takes you into the phase of relaxation.

"If that's impossible, you can do it very simply if you clench your fists and squeeze all the muscles in your arms and shoulders as hard as you can for about three seconds, and then let go.

"You can also try to put yourself under a different kind of stress. Give yourself a different deadline. If you have a piece of work to do, that can be a different kind of tension and quite refreshing."

What of mental trickery? Telling ourselves that it doesn't really matter simply doesn't work, but how about thinking of better times, of losing ourselves in nostalgia or delusions of a brighter future? David Hirst has been retired for over a decade now, but thanks to the vaults of YouTube his unparalleled ability to lift the spirits of certain nameless bloggers remains undiminished.

"The trouble is that your brain is at war with your feelings," says Hodson. "Your feelings are one of dread, yet your brain says, well, these things happen.

"It is helpful sometimes to try to picture an image of when you were quite young, a day when you were gloriously happy. Look at that picture, see what the sky is like, and memorise all the elements.

"Imagine the happy picture and dwell on it in your mind when you're at your lowest. Because it's quite hard for the brain to feel both happy and sad, that can work quite well. It will take your mind off it for a while, and it's the release you're looking for."

An example of what for some people is happy moment from the past (Getty)

"Tis better to have loved and lost, then never to have loved at all," wrote Tennyson, and although Alfred, Lord never experienced the pain of a 4-1 thrashing at rain-soaked Vicarage Road in November, his famous words ring true to this day.

From a philosophical perspective, perhaps we need defeats to truly appreciate the victories. Maybe only through relegation can we truly savour the bliss of a 2-1 win at home to a rudderless Peterborough.

"If you want to feast you must fast," confirms Phillip. "If you want to enjoy your team's sporting success, there must be a contrast. If it was all 6-0 victories, it would be very boring. Being beaten is part of the game.

"Unless you care about the fate of your team, unless you're in love with them on some level, you can't experience that joy. But because you are in love with them, you are going to be let down at some point. Becoming vulnerable to the good stuff makes you vulnerable to the bad stuff. It's what we call unavoidable unhappiness.

"All love ends in pain at some stage. Even if you live happily with a wife or husband for 60 years, someone has to die first."

Fearing we were moving into somewhat morbid waters, I steered the conversation back to practical matters. Should the worst happen and the relegation whirlpool suck your boat down, is it better to drown your sorrows alone or with your fellow shipmates?

"We all grieve in different ways," says Hodson. "The thing is, does your method work? If you want to throw yourself into work for a while, or to tell yourself you don't care, that's fine - it's part of the grieving process. But if it's all about denial, your grief will still catch you up at some stage. You will be ambushed by the bad feelings.

"Anything that helps you get through that time is good. Sometimes the first thing to do is just to accept your feelings.

"It's good to feel, it's horrible not to. If the feeling part of your brain doesn't work, you can't even tell me what you want for dinner."

What of our real-life partners? Despite their best intentions, not all can appreciate what the distraught fan is going through. Can the offer of a cup of green tea assuage the bitter sting of defeat at Middlesbrough to a flukey deflected goal? Experience of those close to the author would suggest not.

"If you know that your partner is upset, don't try to tell them it doesn't matter, or that it's only a sport," advises Hodson. "Instead, say something like, 'I can see you're gutted, I won't say another word'.

"There are many people who can't access football emotionally or mentally. If, for you, football is life and death, yet you're living with someone like that, they need to work quite hard to be supportive.

"It's not about '11 silly men kicking a ball into a net', it's about whether your partner's feelings of distress matter to you. If they don't matter, you don't have a relationship.

"What's interesting is that supporters of the team that wins have a much higher sex drive than supporters of the team that loses, and they often express it. Try to upset that research by making yourself do it that night, or be a great lover, because you'll get a sense of euphoria from it."

So there we have it. Go for a long run, throw yourself into work or put in a blinder between the sheets. Or, should you have the energy, attempt all three. Administration - where is thy sting?

A word of explanation, too: we've all got our own systems, and under mine, you'd only get a 0 if you bagged a pair/went 0-150 and then dropped at least two catches, and only get a 10 if you scored a chanceless double-ton or took at least 10 wickets in an unplayable spell.

ENGLAND

Andrew Strauss - 4
A horrible few days for the England skipper. When he won the toss on Friday, he can have had little inkling of what would unfold in the next few hours. Failed to replicate his form of earlier in the series with the bat and struggled to gain any control in the field, although his bowlers let him down badly.

Alastair Cook - 5
Hung around for a while in both innings without ever looking settled - but then which England batsman did? Fell twice to pokes outside off stump, and has an aggregate of just 203 from seven innings in the series.

Ian Bell - 3
Since coming back into the team, the Bell of 2009 has yet to demonstrate that he's significantly better than the model of previous years. Out-thought by Mitchell Johnson in the first innings, his capitulation in the collapse on Saturday evening was depressingly predictable.

Paul Collingwood - 3
A duck on Friday morning, just four on Saturday - Collingwood was unable to halt the slide on either day. His nemesis Stuart Clark is likely to keep his place for The Oval, which doesn't bode well.

Matt Prior - 7
Continues to impress behind the timbers, even after being incapacitated on the first morning by that back spasm. Some fine takes with the gloves and top-scored in England's first innings, although that's not saying all that much.

Stuart Broad - 8
Came back well from his thumpings at Edgbaston to take six wickets. Old pros complained that he bowled too wide of off in an attempt to stem the flow of runs, but compared to what was served up by his fellow pace bowlers at least it was accurate, and he once again claimed the prize scalp of Ricky Ponting. Another attacking flourish with the bat on Sunday to finally give the home supporters something to cheer about.

Graeme Swann - 5
Not given a bowl until 60 overs of Australia's reply, and then went 16 overs without taking a wicket. Although he found a little turn, he was smashed out of the ground by Stuart Clark and failed to trouble left-hander Marcus North. Attacked entertainingly with Broad on the final morning to lift the Headingley mood and bag his first Ashes half-century.

Steve Harmison - 3
Plus ca change. While Australia's comeback kid Stuart Clark took a fine 3-18, Harmison failed to rise to the occasion. Took the early wicket of Simon Katich but then bowled too short again and again and again. Only in the team because of Andrew Flintoff's injury, his days at international level are surely numbered.

James Anderson - 3
Injured himself while once again avoiding a duck when batting, and struggled with the ball from then on. Wicketless in the Aussie innings and went for almost five an over, failing to find any swing and struggling badly with his control.

Graham Onions - 5
Struggled less than his Durham team-mate Harmison and saw off Watson and Clarke with good in-swing, but dropped short and wide too often as Australia ran away with the match on Friday afternoon.

AUSTRALIA

Shane Watson - 7
An experiment that has worked. Three innings, three fifties. Took the fight to England from the word play, smashing Anderson for consecutive fours from the first two balls of the Aussie innings. His side never looked back.

Simon Katich - 4
Snagged by Harmison's short one - the tactic was still a surprise, rather than a stock ball, at that stage - but took two sharp catches under the lid at short leg. Still averaging over 40 in the series.

Ricky Ponting - 8
Lost the toss and then spent the next two days celebrating the fact. Made the right calls on team selection before the match and carried an upbeat, positive air about him from the moment he arrived in Leeds. Tore into the England bowling on Friday afternoon to take the game even further away from the opposition.

Mike Hussey - 5
Failed to build on the improved showing at Edgbaston and had a quiet time of it in the field. Averaging only 25 in the series and will want a big finish at The Oval.

Michael Clarke - 8
The batsman of the series so far, he continued to play with elegance and style. The only surprise was that he fell seven runs short of his century. Now has 445 runs from six innings at an average of almost 90. What England would give for a middle-order batsman of his class.

Marcus North - 9
Perceived as a weak link before the series began, but has now outscored every batsman in the England team and all but one in his own. Batted with immense concentration as he compiled his second century of the summer and took an outrageous catch in the first hour to see off Strauss and start the England slide.

Brad Haddin - 8
Defied accepted medical wisdom by coming back into the side just eight days after breaking his finger and kept wicket faultlessly. His one-handed catch at full length to see off Matt Prior on Sunday was a beauty.

Mitchell Johnson - 9
Without question, Johnson is back. There was pace, late swing and slingy bounce. His spell on Saturday evening, seeing off Bell, Collingwood and Cook in quick succession, destroyed any hopes England had of a repeat of 1981's Headingley heroics, and his five wickets in the second sealed the win.

Peter Siddle - 8
Tore the heart out of England with five wickets on the first day, including a devastating spell of four wickets in 14 hostile deliveries after lunch. Lost his line and length a little in the second innings as Broad and Swann tucked in, but by then the damage had been done.

Stuart Clark - 7
His control on the first day led many to wonder why it had taken Australia so long to get him back into the team. Bowled beautifully to see off Cook, Collingwood and Broad, fully deserving his haul of 3-18 off 10 testing overs. Enjoyed himself with the bat too, although then took some stick from the England tail at the death.

Ben Hilfenhaus - 9
It seems strange now that his place in the Aussie attack was in serious doubt before the summer began. Has Bopara whenever he wants him, and is the leading wicket-taker in the series. Commendable accuracy, allied with enough bite off the pitch to trouble the best England have to offer.