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Jannik Sinner's defeat also means he will have to wait another year for his chance to complete his set of Grand Slam titles, something rival Carlos Alcaraz did at the Australian Open.

Sinner had already won the Australian and US Opens, and collected the Wimbledon title last year.

But he won't be adding his name to the list of six men - Rod Laver, Andre Agassi, Roger Federer, Rafael Nadal, Novak Djokovic and Alcaraz - who have achieved the full set in the Open era.

No surprises about what the big story of the day is!

But elsewhere...

• 17-year-old Frenchman Moise Kouame has continued his dream run at Roland Garros - he beat Adolfo Daniel Vallejo in five sets to reach the third round.
• Naomi Osaka and Iva Jovic have booked third-round spots in the women's draw.
• Still to come... Aryna Sabalenka, Amanda Anisimova, Coco Gauff and Great Britain's Katie Boulter.

Russell Fuller
BBC tennis correspondent on BBC Radio 5 Sports Extra

It is not easy to be able to play like that against an injured opponent, so a huge credit to Cerundolo for doing just that. This was so impressive, the way he handled it and he never let Sinner back into the match.

I do feel sorry for Sinner, because physically it is more difficult for him to deal with these conditions as a redhead and his complexion makes it difficult.

I don't think we can say that he didn't prepare properly but I would say he has played and won too many matches to get to this point. He was relentless and it was probably a combination of many factors.

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With no Carlos Alcaraz because of injury, and now Jannik Sinner eliminated in the second round, that opens the men's singles draw right up at Roland Garros.

Is this the time for Novak Djokovic to clinch that record-breaking 25th Grand Slam singles title? Will Alexander Zverev finally land his first? Or will someone else emerge from the pack?

We've got a fascinating week and a bit ahead of us in Paris.

Image source, Getty Images

That was Jannik Sinner's first defeat since mid-February, and ends his 30-match winning streak.

It also means that for the first time since the 2023 US Open, someone other than Carlos Alcaraz or Jannik Sinner will win a men's Grand Slam singles title.

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

I thought Cerundolo gave a very humble speech there and it was like he didn't deserve the win but he absolutely does.

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Juan Manuel Cerundolo, speaking on court after his five-set victory over world number one Jannik Sinner:

"It's tough for him, he was leading the match and I couldn't win more than three games in a set.

"I was a little bit lucky and I feel sorry for him, he was serving to win the match. Then I don't know what happened, I think he was cramping. Of course I feel sorry for him and I hope he recovers."

On reaching the third round at a Grand Slam for the first time in his career: "I'm super happy, I will try to keep playing my best. I like to play this tournament because clay is my best surface and I hope to be ready for the next match."

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

This is a seismic shock. So many of us were standing there at the start of this tournament saying who on earth can challenge Sinner for this title?

Everyone was on their feet, I think they were a bit stunned at the way the drama played out. It certainly opens this tournament and send shockwaves through the draw.

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

Carry on and see what happens is good advice from the Sinner camp. It isn't about the tactics any more, it is about the physicality.

The Jannik Sinner of the first two sets is long gone now, but the Italian can still show flashes of brilliance, as evidenced by the ferocious forehand return with which he punishes a nervy second serve from Juan Manual Cerundolo.

Sinner earns a couple of break points but Cerundolo stays strong to hold.

He is now just one game from a famous victory.

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

That was the most pace that Sinner has put in his serve. I don't think he has it in him to do long physical rallies at the back of the court but he has it in him to energise some of the ground strokes. I think we will see him still fight.

A welcome hold for Jannik Sinner, which pleases the crowd.

The world number one walks to his chair and slumps down in it. Can he summon any more energy to deny Juan Manuel Cerundolo the biggest win of his career, and the biggest shock of the tournament?

Sinner had lost 16 of the previous 17 games before that service hold.

Surely there's no way back now for Jannik Sinner as Juan Manuel Cerundolo wraps up another easy service hold.

But can the inexperienced Argentine, the world number 56 who has never reached the third round of a Grand Slam before, hold his nerve as the finish line approaches?

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

Sinner looks like he is about to throw up in the middle of the court, he is not in good shape.

The Chatrier crowd try to give Jannik Sinner some encouragement but Juan Manuel Cerundolo has got the bit between his teeth.

He's moving Sinner around, and the world number one just can't deal with it.

Sinner saves three break points but he's only delaying the inevitable, and Cerundolo breaks when Sinner nets a forehand.

From 5-1 in the third set, Sinner has won just one of the past 16 games.

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

Image source, Getty Images

This is just so impressive by Cerundolo, he just has his head down and isn't distracted by what is happening at the other end of the court. This could be one of the all-time greatest upsets.

It's an easy hold for Juan Manuel Cerundolo.

He looks like he has got used to playing a compromised opponent and is ready to exploit the opportunity.

Jannik Sinner seems determined to give it a go but mishits an overhead on the very first point of the deciding set. Is that an omen?

A long rally finishes with a Sinner error and he then undercooks a drop shot to give Cerundolo an early chance to break.

Sinner is coming to the net when he can now to shorten the points - and even manages to find the energy for fist pump after putting away a volley.

But Cerundolo is chasing everything down and earns the early break.

Annabel Croft
Former British number one on BBC Radio 5 Sports Extra

I just didn't see this scenario happening, no one knew it was going to be this hot, this sweltering, these brutal conditions and I think we underestimate how much it takes out of them. Being out there in this climate is like being in a cauldron or an oven.