| KOHLER, Wisconsin
KOHLER, Wisconsin Tiger Woods's astonishingly poor display at last week's WGC-Bridgestone Invitational has left his rivals bemused and wondering how he will fare in the final major of the year.
The American world number one will tee off on Thursday in the U.S. PGA Championship at Whistling Straits with a myriad of question marks hovering over his game and the emotional state of his mind.
On Sunday at Firestone Country Club in Akron, Ohio -- a course where he had previously reigned supreme -- Woods completed the worst PGA Tour performance of his career.
He signed off with an ugly seven-over-par 77 for an 18-over total of 298, his highest 72-hole aggregate on the circuit and the first time since the 2003 PGA Championship he had strung together four rounds over par.
While Woods has made a habit of producing miraculous recoveries since turning professional in 1996, the 2010 model has spluttered and stuttered through eight winless events on the PGA Tour.
His legendary on-course focus has clearly been distracted by his unraveling private life and he has hinted he might turn to Florida-based swing coach Sean Foley after struggling with every department of his game at Firestone.
Woods has unquestionably lost the aura of invincibility he once enjoyed since his double life was exposed at the end of last year amid revelations of marital infidelities.
"I don't know about entering a new era but there is a slightly different feel, certainly this week," British world number nine Paul Casey told reporters on Tuesday.
"The feeling in the locker room is slightly different. The way he played the past week, guys feel this tournament is wide open, and that's not a feeling a lot of guys have had before."
Fourth-ranked American Steve Stricker was among those stunned by the manner of Woods's Firestone flop.
"It's very surprising, but in this game you need to give total attention and total focus," said Stricker, who partnered Woods at last year's Presidents Cup.
"We all know he's got a lot of other things going on in his life right now, and the game of golf is hard for him right now. You need some positive thoughts and a clear mind. He probably doesn't have that right now, but he'll get it."
Before last week's tournament, Woods conceded for the first time he had been unable to practice as much as normal. With a divorce reportedly looming, he has tried to see his two young children whenever possible.
"Based on what he has said, it would appear that his heart isn't in it quite as much as before," Dr Joe Parent, Vijay Singh's former mental coach, told Reuters.
"One wonders if he is somewhat broken-hearted. We can all identify with that feeling -- of loss, of being somewhat on your own, that the world as you know it is torn apart."
Parent, who helped Fijian Singh become world number one in 2004 and American Cristie Kerr rise to the top of the women's rankings earlier this year, said this did not mean Woods had lost the desire to win.
"Quite simply, the resources he had to call upon before don't seem to be there," Parent added. "What set Tiger apart from anybody else was his ability to recover when he missed a shot.
"But now when he goes to the well, it's just not there. That sharpness, that intensity of focus, is gone. There is a certain level of intensity, of putting your heart into it. If you're broken-hearted, you haven't got the intensity."
American Hunter Mahan beat Woods by a staggering 30 shots on the way to a two-stroke victory at last week's WGC-Bridgestone Invitational.
On Tuesday, Mahan played a practice round with Woods at Whistling Straits and was impressed by what he saw from the game's leading player.
"Seemed like he was trying to hit a bunch of cuts and he was succeeding on every shot. He had great control over his golf ball and his game looked fine," Mahan said.
"I definitely think he can get it back. His talent is still there. He'll find that little thing he needs and he'll get back to his routine. He'll be winning a major before you know it."
If Mahan is right, it could just be that Woods reached his golfing rock bottom at Firestone last week and will begin his recovery at Whistling Straits on Thursday.
(Editing by Frank Pingue)