Rory McIlroy was despairing over the state of his game after yesterday's opening round in the British Open, saying he felt at times "unconscious" and "brain-dead" on the course.
The Northern Irishman collapsed to an eight-over 79, 13 shots off the early lead held by American Zach Johnson.
McIlroy's flop at Muirfield was just the latest in a season corrupted by a change of golfing equipment he made at the start of the year when he was ranked world No 1. "I don't know what you can do. You've just got to try and play your way out of it. But it's nothing to do with technique. It's all mental out there," McIlroy said.
"Sometimes I feel like I'm walking around out there and I'm unconscious. I just need to try to think more. I'm trying to focus and trying to concentrate.
"But I can't really fathom it at the minute, and it's hard to stand up here and tell you guys [the media] what's really wrong
"It's just so brain-dead. Seriously, I feel like I've been walking around out there like that for the last couple of months. I'm trying to get out of it. I just don't quite know why."
McIlroy had earlier in the week hit back at his critics, insisting his game was "heading in the right direction" on the eve of the Open. The Ulsterman has failed to win a tournament all year after changing his management company and deciding to switch equipment providers, from Titleist to Nike.
Some have suggested his high-profile relationship with tennis star Caroline Wozniacki may also be contributing to his decline. McIlroy, however, said that a lack of focus was not the problem. "No, not at all. It's not that at all. No, I'm fully focused on the golf out there," he said.
McIlroy now faces an uphill struggle just to make it through to the weekend and he vowed to try and loosen up his game in a bid to throw off the shackles.
"I want to try to be here for the weekend. But the thing that I need to do tomorrow is just go out there and freewheel it and try and make birdies and try and play with that little bit of whatever it is I have usually," he said.
US Open champion Justin Rose also had a nightmare start, needing 17 holes before bagging his only birdie of the day, and a double-bogey and three bogeys meant that he came in with a disappointing 75.
Nick Faldo's return to Muirfield, where he won the Open twice, failed to find a spark as he struggled to a 79, while "golden oldie" playing partners, Tom Watson and Freddie Couples, also found it tough going with a pair of 75s.
"The golf course is tough, you know. It's hard work. It's like glass now," said the semi-retired Faldo, who was celebrating his 56th birthday.
The only Chinese player in the field, Wu Ashun, ended his round with a five-over 76.
Meanwhile, 2010 Open champion Louis Oosthuizen of South Africa withdrew after nine holes with what appeared to be a leg injury. He also withdrew with injury from last month's US Open.