Rafael Nadal and Roger Federer are on a collision course to meet in the semifinals of the 2012 Australian Open after being paired on the same side of the bracket. The two tennis legends may also be butting heads off the court, however. Nadal took Federer to task before the start of the tournament, calling him out for not being vocal enough on player issues.

At the heart of the spat is the demanding schedule that professional tennis players have to endure. Andy Murray recently threatened to strike if tennis' governing bodies, the ATP and ITF, didn't consider shortening the season or eliminating a few tournaments. Nadal has been outspoken on the issue as well, and thinks Federer should be too.

"We each have our opinion and maybe he [Federer] likes the circuit," Nadal said. "Me too, I like it, and I think it's better than most sports. That does not mean you cannot be better and that you should [not] change things that are bad."

He added:

"I say a lot of good things about tennis, because thanks to this sport I have had experiences in my life I could never have dreamed of, but to finish your career with pain in all areas of your body is not positive. He finishes his career as fresh as a daisy because he is physically privileged, but neither Murray nor [Novak] Djokovic and I are fresh as a daisy."

The typically level-headed Federer has yet to respond. There is a good chance he will wait and let his play on the court do the talking. Either way, one of the best rivalries in tennis should be a little more interesting this year.

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