Mickelson's final round of 64 completed an eight shot turnaround on Wi who was chasing his first win on the PGA Tour.
Playing with Tiger Woods on the final day, Mickelson needed to make a statement early and he did just that with three birdies and an eagle in his first six holes. He had picked up five shots on Woods in that stretch and when Woods missed three consecutive par saving putts in the next three holes Mickelson was essentially on his own.
Mickelson went bogey free through his final round and with a two shot lead as he played the 18th he could afford to be conservative. A four iron from the tee was followed by another, a pitch to 6 feet and the holed putt for birdie.
"Well, regardless of what number it is, it just feels great to win this tournament," said Mickelson responding to the fact that this was his 10th win on tour. "It feels great, because it's a special place for me, Pebble Beach.
"My grandfather having caddied here, such a national treasure, it means a lot to me because I haven't played the last year the way I would like to.
"I felt like my game was so close heading into the season, and yet my scores didn't reflect how I felt I was playing. And to put it together this week and especially the final round with this round just feels terrific, and it gives me a lot of confidence but also inspires me because I believe now more so that what I'm doing is correct and that I'm able to play some of my best golf."
Wi led by three beginning the day but a four putt double bogey at the first was followed by bogeys at the 5th and 6th and his chance appeared to be gone. Realistically it was but to his credit he fought back with five birdies and a bogey from that point including those at his last three holes.
It was Wi's fifth runner-up finish on the PGA Tour although he will be encouraged by the manner he bounced back after being seemingly overcome by the opportunity early on.
"I started off with a 4 putt and that's probably not very ideal," said Wi. "I hung back in there and to come back and shoot even par I was pleased. No regrets out there. I know missed some short putts but I know that I'm a good putter. Second place finish, I'm pleased and disappointed that I didn't get to win but my time will come."
It is the third consecutive week on the PGA Tour where a non-winner has had a substantial lead in the final round only to lose. Kyle Stanley and Spencer Levin (who finished 9th today) showed great resilience in their follow up tournaments and hopefully it will be the same for Wi.
Ricky Barnes and Aaron Baddeley finished their weeks off with rounds of 67 to finish 3rd and 4th respectively. Baddeley's two bogeys n the middle of his round at the 7th and 8th holes were costly but he will be pleased with yet another good start to the PGA Tour. Four starts for four cheques, this one worth US$ 307,000.
Tiger Woods was the centre of much attention this week but faltered over the final round to finish with 75 and a share of 15th.
"What was frustrating is that I had a chance and all I had to do was get off to a good, solid start today and I didn't do that, said Woods. "I was 1"‘under through 6, which Phil was 5"‘under through six, and that was kind of the start I was hoping to get to, 3"‘under through six or something like that. I didn't do it and thought I could get it in the middle part of the round, but instead I went the other way."
Steve Bowditch also had a good week finishing in 15th position in the individual and well up also in the Pro-Am event where he played with entertainer Ray Romano and finished 5th. It was Bowditch's best PGA Tour finish since being placed 9th in this event last year. In just his second start in a season where he is playing on limited status it was an encouraging start.
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