Wimbledon champion Roger Federer has split with his coach Peter Lundgren after the most successful year of his career.
The 22-year-old has been working with the Swedish coach, a close friend, since 1998 and Tuesday's announcement came just three weeks after Federer won the season-ending Masters Cup, thrashing Andre Agassi in the final.
"I just had the feeling I should look for something new. I would like new impetus, and after thinking it over carefully I saw this as a solution for next year," Federer said on Swiss television.
"We both had a bit of a similar feeling at the end of the season that it was not the same as before and this led me to the decision."
No successor has been chosen yet, he said, adding that he wanted to have a trial period with his new coach.
"Peter Lundgren and Roger Federer have gone a lot further than the goals they had set," a statement on Federer's personal website said.
"With the success and the skills that Roger has worked on with Peter Lundgren, Roger Federer is very well equipped for the challenges yet to come. But this also meant the desire for re-orientation in his environment in terms of sport."
Federer won more prize money in 2003 than any other player -- $4 million -- and finished second in the rankings behind American Andy Roddick.
He won the Wimbledon title in July, beating Mark Philippoussis in the final after crushing Roddick 7-6, 6-3, 6-3 in the semi-final in one of the year's great performances.
The shaggy-haired, stocky Lundgren was a familiar sight in the stands at major tournaments and the two men were considered inseparable.