Mired in his worst slump in more than three years, Roger Federer is splitting from coach Tony Roche.
The top-ranked Federer announced the change on his Web site Saturday, saying he and Roche mutually decided to end their arrangement. The move leaves Federer without a coach two weeks before the May 27 start of the French Open, the only Grand Slam tournament he hasn't won.
Roche has worked with Federer part time for the past 2 1/2 years. The Swiss star won six of his 10 major championships in that span.
"I thank Tony very much for his efforts over these last years, during which I appreciated the 12-15 weeks per season we would work together," Federer said on his site. "I am also grateful for the sacrifice he made, traveling so far from his home in Australia and leaving his family."
Roche was with Federer this week at the Rome Masters, where he was upset in the third round by Filippo Volandri, ranked 53rd in the world. That loss meant Federer has played in four consecutive tournaments without winning a title, his longest such drought since he rose to No. 1 in the rankings in February 2004.
"I don't know what's wrong. I have to analyze it myself," Federer said after the defeat in Rome.
He added that he thought he needed to "get back on the practice courts instead of the match courts."
Roche is a former Australian Davis Cup captain who also has coached top-ranked players Ivan Lendl and Patrick Rafter.
Federer has worked off and on with coaches since his longtime coach Peter Carter died in a car crash in 2002. Federer was coached by Peter Lundgren in 2003, then didn't have a coach at all the next year, when he won 11 titles -- including three majors.
He brought Roche aboard before the 2005 Australian Open, working with him in Sydney for two weeks. At the time, Federer said: "I hope he can improve my game just a little bit. I like the way I'm playing right now. If he can improve just a few things in my game, that will be good."
AP Sports Writer Andrew Dampf in Rome contributed to this report.