Alexander Zverev said he suffered torn ligaments after rolling on his ankle and being forced to retire from his French Open semi-final against 13-time champion Rafael Nadal on Friday.

“I am now on my way back home. Based on the first medical checks, it looks like I have torn several lateral ligaments in my right foot,” the German, who was seeded third at Roland Garros, wrote on Instagram on Saturday.

“I will be flying to Germany on Monday to make further examinations and to determine the best and quickest way for me to recover.”

Zverev, who was gunning for his maiden grand slam title and would have taken over as world No.1 had he succeeded in his quest, was 7-6, 6-6 down when he took the tumble that ended what had looked like becoming a memorable contest.

Zverev had to be pushed off the Philippe Chatrier court on a wheelchair.

He later returned to the court on crutches to confirm his retirement. Zverev and Nadal had been on court for three hours and 13 minutes when the 25-year-old’s injury occurred.

In a video posted on the French Open’s Twitter account on Friday, Zverev was heard saying that he feared he had suffered a “very serious injury”.

Zverev backed Nadal to go on and win a 14th French Open title. The Spaniard meets world No.8 Casper Ruud in Sunday’s final.

“I want to congratulate Rafa,” said Zverev. “It’s incredible to see him in a 14th final and hopefully he can go all the way and make some more history.

“But, not an easy moment for me today and I’ll keep everybody updated.”

Written with inputs from Reuters