Mickelson was playing 10 minutes from home, had won at La Costa when the Mercedes Championships tournament used to be held here and he's been playing brilliantly following a winless 2003.
Then again, match play is a free-for-all, with the exit always just a bad round away. After just one day of the five-day tournament, 32 of the world's best golfers are heading home. Two years ago, top seed Tiger Woods, No. 2 Mickelson and No. 3 David Duval were knocked out on the first day.
So first-round winners breathe a heck of a lot easier than they do if they, say, take the lead after the first round of a stroke-play tournament.
'I was fortunate enough to win my match,' a relaxed Mickelson said after beating Westwood, 3 and 1, to stay in the running for the $1.2 million winner's share. 'It's a tournament I really want to do well at.
'I have not played as well as I would have liked in the years past, and I certainly hope that this is a good sign for the rest of the event. I played very well today, tee to green.'
Mickelson, the No. 6 seed, struggled with his putter, but his driving and short game kept him in the match.
'My speed was off the entire day,' said Mickelson, who played a practice round here on Sunday, then didn't come back until Wednesday and found the greens were faster. 'But because I hit the ball in the fairway, hit a lot of greens and was fairly close, I didn't put myself in a bad spot.'
The left-hander jump-started his round with a short birdie putt on the ninth hole to square the match. He then made birdies on the next two holes, both of which Westwood conceded.
Mickelson has started the season with four straight finishes in the top 10, the first time he has done that in his 12-year PGA Tour career. He won the Bob Hope Chrysler Classic on Jan. 25 to end an 18-month winless streak.
Mickelson has made it to the third round twice in the Match Play Championship, losing both times.
'I think that Wednesday, Thursday and Friday, because we have so many more matches, that they seem to be the most exciting days,' he said.
Mickelson plays Thursday against No. 38 Ben Curtis, who beat No. 27 Charles Howell III 2-up.
DOWNHILL ALL THE WAY: Mickelson took last week off to go skiing with his wife, Amy.
'I found that I needed some high-altitude physical training, so I went up to the mountains in Utah and found some snow and went at it,' he said. 'It's a nice escape from golf because you're dressed up in a ski outfit, nobody recognizes you, and you're skiing down the slope, nobody comes up and interrupts. It's a wonderful way to spend a few days.'
FITNESS FANATIC: Darren Clarke lost 30 pounds after going on a health kick that included giving up Guinness in the pub and cigarettes on the course. That might have helped the 35-year-old player from Northern Ireland survive an epic 25-hole match against Eduardo Romero of Argentina.
'I would like to think so,' said Clarke, who won the match with a birdie-3 on the seventh extra hole. 'I feel fine now. I'm going back to the range to hit balls and then I'm going back to the gym.'
Clarke beat Tiger Woods in the championship match here in 2000. Against Romero, he was two down with three holes to play. It was hardly an insurmountable lead for Romero, especially after Clarke birdied No. 16.
'I got one back, so now I'm back one with two to go,' he said. 'One hole makes a huge change mentally, so two down and three to go, no, you're never out of it, not in match play.'
Clarke birdied two of those holes -- including an eagle chip from just short of the 18th green -- to keep the match going. He won it on the 25th hole when Romero made bogey.
NO AIRPORT YET FOR MONTY: No. 52 Colin Montgomerie rallied from two down with three left to beat No. 13 Nick Price in 20 holes. It was just the second time in five Match Play Championship appearances that Monty won his first-round match.
'I was beating myself again, and I'm good at that at this tournament,' the Scot said.
He then sank a 25-foot birdie putt on the par-3 16th to right himself.
'You hole a putt and the whole world seems a different place,' he said.
Montgomerie's second-round opponent is No. 45 Stewart Cink, who beat K.J. Choi 4 and 2.
'My record here is pretty poor, to be honest, bloody awful, in fact, and to get
through round one is a start,' Montgomerie said.
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