Zurich - Roger Federer will attempt to rescue his season and qualify for the World Tour Finals next month without longtime coach Paul Annacone at his side after the Swiss on Sunday announced his split from the American.
"After three superb years of collaboration Paul and I have decided to open a new chapter in our professional lives," the 17-time grand slam champion said with the upmost diplomacy on his website. "Ever since we began working together, we had established a three-year plan to win grand slams and return to the number one ranking.
"We reached those objectives. After numerous conversations and the end of our most recent training block we decided that this is the best moment to go our separate ways.
"Paul remains a good friend and I respect his perspective. Thanks to Paul for his support of my team and I over these three years."
Federer will go to work after losing in the Shanghai third round to Gael Monfils to try and claim a spot in the year-end final next month in London.
He will have to do so over only two events, his home Swiss Indoors in Basel starting a week from Monday and the final Master 1000 of the season at Paris Bercy.
By his world-class standards, Federer has had a poor season, winning a title at Halle and exiting relatively early early at Wimbledon and the US Open. He has been passed in the race to London by good friend and compatriot Stanislas Wawrinka.
Annacone gave a shout-out to his former employer in a tweet: "Thx RF & Team RF - been a terrific journey - great team, better people!!! Thx to all !!!"