Novak Djokovic’s coach Goran Ivanisevic believes that Roger Federer may not win another Grand Slam title before he retires.

Ivanisevic was speaking in an interview on Nova TV when he explained his prediction that both Djokovic and Rafael Nadal will break Federer’s record for majors won.

“When one day everyone finishes their career, then an account will be made,” he said.

“It’s hard for me to talk here because in my opinion Novak is the best and he is the only one who can win a calendar Grand Slam.

“If he’s healthy, I think he’ll break that record. I think Nadal will break Federer’s record as well.”

Roger Federer is currently the most decorated male tennis player in history with 20 Grand Slam titles. Rafael Nadal is one behind on 19, with Djokovic on 17.

“Unfortunately, I don’t think Federer will win any more Grand Slam, because he certainly won’t come back younger,” Ivanisevic continued. “But Federer should not be written off.

“Novak Djokovic is the greatest tennis player of all time for me, and I sincerely hope that he will do it as a result.”