Five-time major champion Phil Mickelson said on Tuesday that a recent six-day fast to "reset" after a poor run of form has helped him "feel better" about himself heading into this week's Open Championship.
The 49-year-old, who was presented with an award at Royal Portrush for 25 consecutive years ranked in the world's top 50, said he lost 15 lbs (6.8kg) after only drinking water and a "special coffee blend" for six days.
"The first day and a half was tough, but after that I found that I didn't crave food, I felt better, my energy levels were better, my focus was better," said Mickelson.
I just started to reset my mind and body and that's just the start.
I want to take it from there and continue to feed both my mind and body with positive nourishment to get the best out of me.
The left-hander has been ranked in the top 50 for over 1,300 successive weeks since November 2013.
But Mickelson has slipped from 17th to 28th in recent months, missing four cuts in his last six tournaments, and admits his fast may not bring about an immediate upturn in form.
"I don't know if it's going to help me play better, but it certainly helps me feel better about myself and feel better throughout the day," he added.
Mickelson, who has never reached the world number one spot, fell to 49th in the rankings in 2018 before a strong run of form, capped by victory in the WGC Mexico Championship, sent him soaring back into the top 20.
"At that point, as soon as I was threatened of going out (of the top 50), I was aware, yeah," said the 2013 Open champion.
I think I ended up winning a week or two later in Mexico. As I slide (down the rankings) recently, I'm going to make some changes to get that back.
The American will start his tilt for a sixth major and second Open title on Thursday at 0852 GMT, playing with South African Branden Grace and Ireland's Shane Lowry.
He has no plans to slow down, even though he will turn 50 next June and becoming eligible for the Champions Tour.
"I've had up and down times throughout my career, but my passion for the game and my love for this game of golf always consumes my thoughts and still does to this day."