Manager Martin O'Neill expects Celtic to come under severe pressure in their Champions League play-off second leg - but stressed they will not simply try to protect their advantage.

They lead Austrian champions LASK 3-0 from the first leg and arrive in Linz on the cusp of a return to the league stage.

O'Neill cautioned straight after that impressive victory that the tie was not over, given LASK created a series of chances and had two goals chalked off for offside.

"They will get opportunities to attack and they are a formidable team, there's no question about it," said the Celtic boss, who hopes to have defender Austin Trusty available after a stomach upset caused him to miss training on Monday.

"I expect to be put under pressure quite a lot, but we just can't sit in there, and that's not our intention at all.

"I feel as if we're capable of scoring a goal in the game, and that's at least grounds for optimism. It'll be a tough old night for us, but we're capable.

"We want to try and get through. We'll throw absolutely everything at it to do so.

"I think that if we could qualify, it would give us a massive lift in every aspect."

Celtic have won all four of their matches this season, scoring 13 goals and conceding just one, while LASK had opened with four domestic victories before their visit to Glasgow last week.

Liam Scales is an obvious replacement if Trusty does not recover and teenage full-back Colby Donovan is expected to continue in the absence of Alistair Johnston, who is expected to be sidelined until October.

LASK boss Dietmar Kuhbauer admitted the hosts will need to "take risks", vowing to "fight until the very end".

The 55-year-old, in his second spell at the club, said: "We'll have to throw everything at them, the kitchen sink.

"If it's late in the game, you have to take away defensive players and throw on attacking players. A lot needs to happen. Everyone speaks about getting a quick goal which would be good for the team.

"One goal can make a huge difference and give us a chance of turning the game around. The most important thing is that we hit the right gear as soon as we can."