Accenture World Match Play champion Geoff Ogilvy admits "brains are sometimes not my best attribute" but has advised Tiger Woods' opponents not to upset him in Tucson this week.

"Tell him how good he is and you might have a chance," said Ogilvy, not disappointed to find himself in the opposite half of the draw to the world number one who is trying to make the event his eighth consecutive US Tour win.

"Just don't say anything bad. He won the first nine holes last year after Stephen (Ames) ruffled him up a bit."

Canadian Ames was a late replacement for Thomas Bjorn and the rank outsider of the 64-man field in San Diego, but he unwisely commented he was far from resigned to defeat, "especially where he hits it".

Woods then birdied the first six holes and won by a tournament record nine and eight.

Fellow American JJ Henry is first in line for the top seed on Wednesday, while Ogilvy opens his defence against 2001 winner Steve Stricker.

Last year the 29-year-old from Adelaide was not in the world's top 50 and was the underdog in every match he played en route to the title and a first prize of US$1.3million (almost £650,000).

This time he is not only the holder, but also the US Open champion.

"I snuck through the first four rounds, extra holes every time, and the lucky one was with Mike Weir - he let me off the hook a couple of times," recalls Ogilvy, who also knocked out Michael Campbell, Nick O'Hern, David Howell, Tom Lehman en route to the 36-hole final against Davis Love.

"I played better as the week went on and it's an unbelievable finish when you're the only two people on the golf course. You don't get that experience a lot.

"It was the biggest win of my career to that point. The US Open might get a little bit in front of it, but I probably wouldn't have won the US Open if I didn't get to win this tournament.

"It's a career-builder, when you win something like this."

Not surprisingly given his success, Ogilvy likes the do-or-die nature of match play.

"If you look at a 72-hole stroke play tournament it's a whole week's work, a four-day project, whereas 18-hole match play really is hole by hole.

"What the other guy does really influences what we do. It shouldn't do, but it kind of does. Really you spend the whole day watching what your opponent is doing.

"In a stroke play event you don't really think about that until the last few holes of the golf tournament.

"More crazy stuff happens in match play than will ever happen in stroke play. You'll see a guy chip in to go down extra holes or you'll see a guy win four holes in a row or hole three 30-footers in a row.

"The Ryder Cup is the pinnacle of that sort of stuff happening. Maybe it's because if you don't chip this in, the hole is over. Something happens.

"It might be frustrating to play it every week, but once or twice a year it's fantastic."

Wednesday's first-round includes four all-European games - Padraig Harrington against Lee Westwood, Sergio Garcia against Darren Clarke, Colin Montgomerie against Johan Edfors and Luke Donald against Miguel Angel Jimenez.