KOHLER (Wisconsin) • The most stark warning yet regarding the challenges Rory McIlroy will encounter on his return to action at the US PGA Championship has arrived from Tiger Woods.
The 14-time Major winner, whose career has been blighted in part by injury, fears the slopes of Whistling Straits may undermine McIlroy's ability to successfully defend the Wanamaker Trophy this week.
The 26-year-old Northern Irish golfer has missed more than 50 days of competitive golf, including the Open, after rupturing an ankle ligament during a football match with friends in Northern Ireland.
TAKING PAINS TO CAUTION RORY
Is he probably going to be in pain? Probably, yeah. Swelling is going to probably occur but that's why the physios are there and I'm sure they'll get him organised.
TIGER WOODS, on the prospects for the US PGA defending champion
The world No. 1 has looked in ideal physical condition in Wisconsin, where he has practised every day since Saturday and declared the ankle scenario a "non-issue".
Woods, though, is not so sure.
PGA CHAMPIONSHIP: THE CONTENDERS
DUSTIN JOHNSON (USA)
31 years, world No. 7
He tied for sixth at The Masters, tied for second at the US Open and played well before fading to a tie for 49th at the Open. His Major form is good this year. It would be amazing if he wins this week as his penalty-shot gaffe kept him from a play-off in 2010 at Whistling Straits.
JORDAN SPIETH (USA)
22 years, world No. 2
He is on course to sweep all three US Majors in the same year, having won the first two. He also missed the Open play-off by one shot. He will be a major factor at Whistling Straits as long as he putts steadily.
JASON DAY (Aus)
27 years, world No. 4
He had vertigo problems at the US Open and was close to making the play-off at the Open. The affable Australian has shown that he has the game to win a Major - recording nine top-10 finishes in 20 career Majors. It will be his time if he can channel his temperament and stay healthy.
RICKIE FOWLER (USA)
26 years, world No. 5
He has not had an exceptional time at the Majors this year, after finishing in the top five at all four last year. Yet, he is a force to reckon with, especially with his confidence bolstered by his success at The Players Championship and Scottish Open. He loves to perform on the big stage.
RORY MCILROY (Nir)
26 years, world No. 1
Will his injured ankle stand the strenuous test this week? And does he have the form after not competing for two months? He has the experience to win it, though, and good memories from Whistling Straits where missed the play-off by one shot in 2010.
"Am I surprised he's made the recovery? No, not really," Woods said on Tuesday. "He has good physios, he has worked hard.
"It's a matter of how long is he going to have to go with it like this or is he going to have to get it surgically repaired.
"And then, obviously, this is going to be tough. This is going to be a tough golf course if you miss the golf ball a little bit. Even the walks, from tee box to fairway, they're not straight. They've got a little undulation and it's just a matter of how can he hold that up.
1st round (selected, Singapore time)
8.35pm Thongchai Jaidee (Tha)
Tomorrow, 2am Luke Donald (Eng), Graeme McDowell (Nir), Patrick Reed (USA)
2.10am Adam Scott (Aus), Henrik Stenson (Swe)
2.20am Rory McIlroy (Nir), Jordan Spieth (USA), Zach Johnson (USA)
7.55pm Hideki Matsuyama (Jpn)
8.05pm Colin Montgomerie (Sco), John Daly (USA)
8.15pm Victor Dubuisson (Fra), Matt Kuchar (USA), Charl Schwartzel (Rsa)
8.25pm Sergio Garcia (Esp), Louis Oosthuizen (Rsa)
8.35pm Justin Rose (Eng)
8.45pm Bubba Watson (USA), Paul Casey (Eng), Jim Furyk (USA)
8.55pm Hunter Mahan (USA), Lee Westwood (Eng), Ernie Els (Rsa)
9.05pm Jason Day (Aus), Dustin Johnson (USA), Rickie Fowler (USA)
9.15pm Tiger Woods (USA), Martin Kaymer (Ger), Keegan Bradley (USA)
Tomorrow, 1.30am: Yang Yong Eun (Kor)
"As far as his talent and to be able to play golf, that's not going to be a problem. He understands how to play. It's a matter of physically can he do it."
Woods added: "I blew out my knee and played for a good nine months before I had it fixed, so it can be done. Is he probably going to be in pain? Probably, yeah. Swelling is going to probably occur but that's why the physios are there and I'm sure they'll get him organised."
Woods' view is at odds with McIlroy's compatriot Darren Clarke. Europe's Ryder Cup captain said it would be no shock at all to see McIlroy challenging for the lead on Sunday.
"I'm sure with an ankle injury he would have been advised not to come back until fully fit," Clarke said. "If you injure an ankle and keep playing on it, it gets worse and worse and worse.
"He's back, he may not be competitively sharp for obvious reasons but he's the world No. 1. He's done many amazing things in his young career, so I wouldn't be surprised to see him contending this week."
Clarke shrugged off the prospect of American players taking all four Majors this year. Jordan Spieth and Zach Johnson have the first three between them. "If you ask me the same question next year I may be a little more concerned," he said.
It is a sign of Woods' lowly status - he is ranked 278th in the world - that his pre-tournament media conference was dominated by talk of McIlroy, the 23-year-old Hideki Matsuyama, the veteran Steve Stricker and a new restaurant venture in Florida. The notion of winning a 15th Major has never been so detached from the Woods story.
"I don't know my exact ranking right now," Woods said. "I know I'm in the 200s somewhere. As far as paying attention to it, no, I'm just trying to get better. I'm just trying to get up there where I can win tournaments, get my game organised, so I can be consistent on a tournament basis where I'm going to give myself a chance to win each and every event I play in.
"That's what I have done over most of my career - and I'd like to get to that point again where I could do that."
Day 1: Singtel TV Ch115 & StarHub Ch209, tomorrow, 2am