Novak Djokovic's Olympic quest in doubt as knee injury clouds semi-final match

The 37-year-old beat Tsitsipas 6-3 7-6 (3) to set up a semi-final meeting with Italy's Lorenzo Musetti on Friday, but the 24-time grand slam winner is uncertain if he will be fully fit for action after taking a medical time out while trailing in the second set.

Djokovic damaged his knee when playing in the French Open at Roland Garros in June, subsequently undergoing surgery on a torn meniscus, before returning to action at Wimbledon where he lost in the final to Carlos Alcaraz.

He said: "I'm concerned about the state of the knee. I cannot give you exact information, because I don't have it. I have to go and examine the knee now with my physio and with the medical staff of the tournament. And then let's see."

Iga Swiatek's 25-match winning run at Roland Garros was ended by Zheng Qinwen in a huge upset.

Swiatek has dominated on the Parisian clay, winning four French Open titles in the last five years and three in a row, but the best she can now hope for is a bronze medal after falling to a 6-2 7-5 defeat.

The Pole led 4-0 in the second set as she appeared to have turned the match around, but China's Zheng won four games in a row and eventually clinched victory against a frustrated Swiatek.

It is the world number one's first loss at Roland Garros since she was beaten by Maria Sakkari in the quarter-finals of the French Open in 2021.

Swiatek did not shake the umpire's hand at the end of the match and broke down in tears during a TV interview before declining to speak to written journalists.

Australian Open finalist Zheng, meanwhile, becomes the first Chinese player to reach an Olympic tennis final

She had lost all six previous matches against Swiatek, and the 21-year-old said: "This means everything to me because finally I broke the stage I always have in my head, I finally showed I could beat the world number one on her best surface, at Roland Garros. It really does mean everything.

"I'm so happy that I can make this history for Chinese tennis. I always wanted to be one of the athletes who can get a medal for China, for our country, and right now I'm one of them. I've made history already but I don't want to stop here."

Zheng will face Croatia's Donna Vekic in the final.

Carlos Alcaraz guaranteed himself a shot at a medal with a 6-3 7-6 (7) victory over American Tommy Paul to reach the men's singles semi-finals.

The 21-year-old picked himself up after the disappointment of Wednesday night's doubles loss with Rafael Nadal, recovering from 5-2 down in the second set.

There is guaranteed to be a new champion, with Tokyo gold medallist Alexander Zverev losing 7-5 7-5 to Musetti.

Musetti, who reached his first grand slam semi-final at Wimbledon where he lost to Djokovic, has maintained his good form on the clay and becomes the first Italian to reach the last four in Olympic singles in the modern era.

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