"That sums up my week nicely," he said.
The defending champion overcame the loss of his caddie to cancer to finish second on the overall standings.
Twelve months ago, she was No.1... now she's No.100.
The world No.635 converted back-to-back birdies on the final two holes for victory.
The veteran is in a two-way tie for first at the midway point in Phoenix and on course for a mammoth payday.
Lydia Ko has clinched third place in defence of her title in South Korea.
The world No.13 won this tournament 12 months ago en route to LPGA Player of the Year.
The American becomes just the third woman to break par at a PGA tournament.
Ryan Fox carded a stellar final round in defence of the title he won last year to take home another hefty cheque.
