Rafael Nadal, the former World No 1, is moving to a heavier-headed racquet this season in hopes of improving his serve. He acknowledges it could hurt his game in the short run. Karim Jaafar / Agence France-Presse.

A?day after a rare crack opened up, Roger Federer and Rafael Nadal quickly restored diplomatic relations.

Nadal had criticized Federer for his unwillingness to speak out on issues affecting the men's game, allowing others to "burn themselves" as they seek improved conditions for players.

Federer said "things are fine" between the two rivals, although he concedes that they disagree on a way to resolve a list of player grievances which includes the length of the season and the distribution of prize money.

"We can't always agree on everything," he said. "So far it's always been no problem really. Back in the day he (Nadal) used to say, 'Whatever Roger decides, I'm fine with.' Today he's much more grown up. He has a strong opinion himself, which I think is great."

For his part, Nadal apologized for airing his disagreement with Federer in public - although he didn't back down on the views he expressed.

"Probably I am wrong telling that to (the media), especially because these things can stay, must stay in the locker room," Nadal said.

"I always had fantastic relationship with Roger. I still have fantastic relationship with Roger. Just I said we can have different views about how the tour needs to work. That's all."

The rift emerged following a player meeting on Saturday after talks of a possible strike in six months.