FORMER US amateur champion Phil Mickelson chipped in for birdie at the final hole to clinch a two-stroke victory at the 51.25 million Nortel Tucson Open yesterday. Mickelson shot a closing five-under par 67 at Tucson National for his third Tucson victory in the past six years.

He finished at 14-under 273, while fellow American Bob Tway (67) was second on 275. Tway held the outright lead with four holes left, but two late bogeys cost him dearly.

Lee Janzen, the 1993 US amateur champion. was the only other player in contention late, but he bogeyed the final hole to fall back into a four-way tie for third on 276.

Mickelson, 25, began the final round two strokes behind overnight leader David Toms, who finished equal ninth after a closing 74. Mickelson birdied five of the first 15 holes, before missing a short putt to bogey the par four 16th, his only blemish of the day.

That error reduced his lead to one stroke, but after parring the 17th, he closed magnificently with a deft chip at the last to secure his sixth PGA Tour victory. Mickelson, who lives in nearby Scottsdale, a suburb of Phoenix, first won here in 1991 while still an amateur, and he also won as a professional last year.

This is a really satisfying victory," said Mickelson, who won all three of his "matches in a losing American cause at the Ryder Cup last September. It's been a year since I won and it means a lot. I haven't played golf with this intensity since the Ryder Cup. Last year I made a couple of small changes to my swing in an effort to make my misses less severe. To see it pay off is really satisfying.

Mickelson also explained his affinity with Tucson: "It's so close to home, the courses are 50 similar to those I play in Phoenix, there's not much of a transition."

Tway, meanwhile. was seven under for the day after 14 holes, but he hooked his tee shot out of bounds at the 15th. "I might have tried to hit the drive too hard. It was a low hook with nothing to stop it. Disaster can come at any time," said Tway.