Goran Ivanisevic says Rafael Nadal can potentially break Roger Federer's Grand Slam record, but believes the 17-time Grand Slam champion is the better player.

"I love Rafa, he is a leftie and a great competitor but you have to go with Roger Federer [as the better player], because he is one of the best of all time," Ivanisevic told NDTV Sports.

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The left-handed Croatian, who became the first wild card to win a Grand Slam championship when he defeated Patrick Rafter in the 2001 Wimbledon final, says Nadal can break Federer's Grand Slam record.

"Rafa is a fighter and he is never going to give up," Ivanisevic told NDTV Sport. "He will just fight and fight and if he believes he can do it then that's good enough for me."

Though Federer has not won a Grand Slam title since the 2012 Wimbledon, Ivanisevic said he believes the 33-year-old Swiss can collect another major crown.

"I think so! Last year he played well, he didn't win a Grand Slam but he really played very good tennis," Ivanisevic said. "So you can never underestimate Federer. As soon as he steps on the court, you better beat him or otherwise he is not going to be easy on you and that's why I think he can still win a Grand Slam."