Defending champion Novak Djokovic has withdrawn from the French Open before his quarter-final with a knee injury.

Serbias Djokovic had a scan on the injury on Tuesday, having blamed the "slippery" Roland Garros clay courts for aggravating the problem during his fourth-round victory on Monday.

The top seed announced his withdrawal from the Grand Slam tournament later on Tuesday.

The 37-year-old was due to play Norwegian seventh seed Casper Ruud in the last eight on Wednesday.

The scan revealed Djokovic has torn medial meniscus in his right knee.

"I am really sad to announce that I have to withdraw," Djokovic said.

"My team and I had to make a tough decision after careful consideration and consultation."

The injury has ended his hopes of winning a 25th Grand Slam title - which would be an outright all-time record - on the Paris clay.

Djokovic will also lose his status as the world number one and be replaced by Italy's Jannik Sinner after the French Open.

It remains to be seen if he will be able to regain fitness in time for Wimbledon, where he is a seven-time champion.

The grass-court championships start at the All England Club on 1 July, while the Paris 2024 Olympics begin at Roland Garros on 27 July.

Djokovic has not won an Olympic gold medal and made no secret that it was a key priority this year.