Final Round Leaderboard -7: B Haas, P Mickelson -5: S Garcia (Sp), J Walker -4: B Van Pelt, JB Holmes-3: A BaddeleyPACIFIC PALISADES – Bill Haas clinched his fourth PGA Tour title by beating fellow Americans Phil Mickelson and Keegan Bradley in a gripping sudden-death playoff at the Northern Trust Open on Sunday.The 29-year-old Haas sank a curling 43-foot birdie putt at the second extra hole, the driveable par-four 10th, to seal victory in breezy afternoon sunshine at Riviera Country Club."I never expected to make a 40-footer, and especially in that situation,” a beaming Haas told reporters after clinching the winner’s cheque for nearly $1.2 million."That was a little bit of luck involved, but I felt like I put a good roll on it. It was meant to be, I guess.”Mickelson, seeking a second consecutive PGA Tour win, missed his birdie chance from the back right bunker while Bradley’s attempt, a 15-foot putt from the fringe, slipped past the right edge of the cup.Bradley, winner of last year’s PGA Championship, had set up his birdie opportunity by splashing out of the front right greenside bunker, a shot he described as his best all week.The trio had finished the 72 regulation holes on seven-under-par 277, Haas closing with a two-under 69 while Mickelson and Bradley each birdied the par-four last for matching 71s, Mickelson holing a 26-footer and Bradley following suit with a 13-footer