Roger Federer has split from his American coach Paul Annacone with the struggling Swiss former world tennis number one saying it's the best time to make a change.
The 17-time grand slam winner Federer, sitting seventh in the rankings and attempting to pull his career out of its worrying tailspin, revealed he was calling time on his relationship with Annacone, who guided Pete Sampras during the American great's glory years.
Federer says that after a terrific three and a half years working together, the pair have split, after a three-year plan to win another grand slam title and get back to the number one ranking, which were achieved.
The Swiss great says Annacone remains a dear friend.
Annacone started with Federer in August, 2010, and the American took the Swiss star to a seventh Wimbledon title in 2012, his most recent major.
Federer's announcement comes just two days after losing in the Shanghai Masters third round to Gael Monfils.
That was his first tournament since losing in the US Open fourth round.
Federer's incredible record of 36 consecutive grand slam quarter-finals ended abruptly in the second round at Wimbledon where he was beaten by Sergiy Stakhovsky, who was world No.116 at the time.
Federer, who has carried a back injury for most of the year, has won just one title in 2013 and is in danger of missing out on next month's eight-man, end-of-season World Tour Finals, which he has won a record six times.
But the man who has spent a record total of 302 weeks at world No.1 insisted in Shanghai that he could turn his career around.