Mahan's only previous victory came at the 2007 Travelers Championship in Hartford although he has been considered a potential star of the PGA Tour since joining the Tour for the first time in 2004. Still only 27 it might be now that the flood gates open.
Until this week it had not been a great West Coast Swing for Mahan but today he put together a powerful finish to force his way to the top of an incredibly congested leader-board.
Early on day four it appeared the event might develop into a battle between Scott Piercy, Rickie Fowler and Joe Ogilvie but Y.E. Yang entered the fray when he holed his second from 110 yards at the 10th to move closer and when the Korean birdied the 12th, 13th, 14th and 15th he had the lead on his own.
Just when he appeared to control the outcome, Yang pulled his tee shot at the short but demanding par four 17th and took bogey and he was unable to repair the damage at the 18th.
Mahan eagled the 13th when he produced a superb second from 260 yards to 8 feet and added further birdies at the 14th and 16th to move to 16 under and held the lead.
As Yang, Ogilvie and others dropped off it would be the brilliant rookie Fowler who took up the challenge. He birdied the 14th and 15th holes to move within one of Mahan but at the par five 15th he made a decision that he may now be ruing.
With 230 yards to the flag he decided to lay up and in doing so cost himself the all important birdie he needed to move into a share of the lead. He had another chance at the 16th when his tee shot finished 15 feet from the hole but at the almost reachable par four 17th, he missed the fairway right, got himself out of position, and could only make par.
Fowler's final chance came at the 18th where he produced a fine second from an awkward lie. He faced a 30 foot putt to force the playoff but was unable to do so and for the second time in his very young professional career he would finish runner up.
Fowler's time will come, and before too long, but this would be Mahan's week.
Finishing alone in third position was Y.E. Yang with Australia's Mathew Goggin, a local resident in Scottsdale, powering home to finish 4th with Chris Couch and Charles Howell
Goggin produced a stunning final nine holes. Out in 38 and going backwards in a hurry, Goggin somehow found a way to turn the momentum around, a 65 foot eagle putt at the 13th a highlight. He was home in 30 for 68 and at 13 under par he earns US$248,000 for his efforts this week.
Robert Allenby looked a big chance to win his first PGA Tour event in eight years when he moved within two shots at the turn but his challenge was extinguished when he bogeyed the 11th and then the 18th to eventually finish 8th.
Greg Chalmers finished 24th, Nathan Green 51st, Geoff Ogilvy 62nd and Aaron Baddeley and Michael Sim 74th.