Cameron Norrie attempts a couple of serves but he is clearly struggling with his ribs and his breathing.

Such a disappointment for the British number one, who has never previously retired during a match.

Adolfo Daniel Vallejo of Paraguay has won on his Grand Slam debut.

Annabel Croft
Former British number one on BBC Radio 5 Live

When you're coping with some kind of injury like this, you're sort of sussing it out every time you move or hit the ball, you're assessing it all the time and I think losing the first set would have been so huge in his head - knowing he's got to fight his way through it.

Cameron Norrie is carrying on - for now at least - but can't make any inroads into Adolfo Daniel Vallejo's serve.

The Briton is really up against it now.

Cameron Norrie is not looking happy and has another chat with his team at the change of ends.

Now the doctor comes out and it looks like the rib injury that has prevented him from practising is once again impeding him.

Cameron Norrie went over to his coaching team in the break between sets and there was some intense discussion along with some shoulder-shrugging from Norrie.

It doesn't appear to have any positive impact, as Norrie throws in two double faults, one of which concedes the game.

Image source, Getty Images

Image source, Getty Images

The defending champion will soon take to the clay on Court Philippe Chatrier, where Coco Gauff returns following her triumph over Aryna Sabalenka in the 2025 final.

Gauff became the first US woman to win the title in Paris since Serena Williams in 2015, as she celebrated her second Grand Slam triumph after the 2023 US Open.

The 22-year-old faces 75th-ranked compatriot Taylor Townsend in her opening match as she bids for back-to-back successes.

Four set points saved, one of one taken for Adolfo Daniel Vallejo.

Cameron Norrie will be left scratching his head over how he failed to take that opening set from such a dominant position in the tie-break.

The British number one has a real fight on his hands here!

Image source, Getty Images

After all his good work to level the tie-break, Adolfo Daniel Vallejo double-faults to give Cameron Norrie a fourth opportunity.

But the Briton finds the net with a backhand - and now he must attempt to save a set point for the first time.

Three set points come and go for Cameron Norrie.

Huge credit to Adolfo Daniel Vallejo there, pulling out some terrific shots. He was 5-1 down in the tie-break, but this is anyone's set now...

Cameron Norrie appears in charge of a rally but nets a forehand on his first set point.

Another miss, after he is pushed to the back of the court, leaves him with just one more.

Cameron Norrie has upped his level when it matters at the end of this first set, while Adolfo Daniel Vallejo begins to fall away in the tie-break after an otherwise solid set of tennis.

A double fault gifts Norrie three set points.

Annabel Croft
Former British number one on BBC Radio 5 Live

44 minutes they've been out here and you imagine if the sets are going to be drawn-out like this, it's going to be drawn into a physical battle which is what Norrie absolutely loves.

Then youth down the other side, just 22 years of age, and just watching Vallejo walk you can see he's got an abundance of energy

Adolfo Daniel Vallejo investigates the ground after having a backhand called out, and accepts it missed the line as Cameron Norrie keeps the tie-break on serve.

And it looks like he may have broken Vallejo's resistance here, as the Paraguayan hits long and falls three points behind.

Cameron Norrie throws in a little serve and volley to surprise Adolfo Daniel Vallejo, and the Briton does force a tie-break.

Just the one break point across the opening 12 games. Who will be first to blink?

So, it's back over to Cameron Norrie to try and stay in the first set - this time taking us to a tie-break.

A missed forehand gives Adolfo Daniel Vallejo encouragement at 15-15.

Image source, Getty Images

Cameron Norrie loses out to Adolfo Daniel Vallejo in a battle of the drop shots as the Paraguayan avoids a tricky scoreboard situation following an opening double fault.

Vallejo shakes his racquet as he unleashes his 13th winner of the contest - an accurate forehand down the line - on his way to safety.

'Come on!' yells Cameron Norrie.

A big forehand flashes down the line as the British number one holds with a third successive point. Great response.

There's been little to separate these two so far, but Cameron Norrie finds himself serving to stay in the first set.

He's under real pressure as he nets while scuttling back to the baseline for 15-30.

Annabel Croft
Former British number one on BBC Radio 5 Live

That was impressive serving from Vallejo. He is really getting quite a few free points off it - great accuracy, he's mixing it up well and he looks very at ease on the court.

A stunning two-handed backhand from Cameron Norrie keeps the British number one within touch at 40-30, but Adolfo Daniel Vallejo holds his nerve to move a game away from the set.