Phil Mickelson and swing coach Butch Harmon announced on Wednesday they have decided to part ways after an eight-year partnership that brought two majors among 12 PGA Tour victories.
Mickelson, 45, has slipped to 25th in the world after back-to-back winless seasons.
He said in a statement released to golf.com that he had improved a great deal after working with one of the sport's greatest teachers but that he was looking for a fresh approach.
"I’ve learned a great deal from him in our eight years together. It's just that at the moment I need to hear new ideas from a different perspective,” said Mickelson, who last recorded a victory at the 2013 British Open.