LA QUINTA, 26 Jan, 2015 (AFP) - "This is unbelievable. This is great," said the 32-year-old Haas.
Haas shot a final round 67 to finish the week at 22-under-par 266 and win for the sixth time on the PGA Tour. This is Haas's second victory at this event, which he also won five years ago.
"I was fighting it today," Haas said. "You can see on the last hole that I was grinding it out to the end.
"I was lucky enough to make a couple of putts. The one on No. 16 was huge. I knew I needed that one to at least give me a chance here on 18."
Coming down to the par-five final hole, Haas needed a par to win. A bogey by Haas would have forced a six-way playoff, which would have tied a US Tour record. Haas was able to scramble for par and win on the Arnold Palmer Private Course.
Second-round leader Matt Kuchar finished with a five-under 67 and he ended tied for second along with Charley Hoffman (64), Brendan Steele (64), Park Sung-Joon (65) and Steve Wheatcroft (67) at 21-under 267. Kuchar was the highest ranked player in the tournament.
Rookie Justin Thomas, who shared the third-round lead with Haas, Erik Compton and first-round leader Michael Putnam, finished with a three-under 69 and tied for seventh with Webb Simpson (64) and Boo Weekley (65) at minus-20.
Compton could not make enough birdies down the stretch and he carded a two-under 70 to finish tied for 10th at 19-under 269. Putnam (72) ended two shots behind Compton at 17-under 271, tying him for 15th.
Defending champion Patrick Reed needed to go low on Sunday to try and defend his title, but he fired a one-under 71 to finish tied for 24th at 15-under 273 with Phil Mickelson (68).
Leading scores after Sunday's fourth round of the US PGA Tour's $5.7 million Humana Challenge (USA unless noted, par-72):
266 - Bill Haas 67-63-69-67
267 - Matt Kuchar 65-64-71-67, Charley Hoffman 71-63-69-64, Steve Wheatcroft 65-67-68-67, Brendan Steele 67-68-68-64, Park Sung Joon (KOR) 68-67-67-65
268 - Boo Weekley 70-66-67-65, Webb Simpson 70-66-68-64, Justin Thomas 68-63-68-69
269 - Erik Compton 66-66-67-70, Ryan Palmer 71-61-68-69, Francesco Molinari (ITA) 64-71-67-67, Colt Knost 71-67-68-63
270 - Nick Watney 67-64-71-68
271 - Alex Cejka (GER) 68-64-70-69, Lucas Glover 68-69-66-68, Martin Laird (SCO) 68-66-68-69, Michael Putnam 63-67-69-72, Shawn Stefani 75-66-63-67