The winner of the PGA Tour's 2014 Puerto Rico Open, the 30-year-old Hadley finished with a tournament-record 23-under 265 total on Peek'n Peak's Upper Course. He earned $108,000 to jump from 22nd to fourth on the money list with $218,450, more than enough to wrap a return to the PGA Tour as a top-25 finisher.
"That was the goal this year," said Hadley, who finished 159th last season in the PGA Tour's FedExCup standings. "I know I had tour status -- it's not great tour status, but it's still tour status, which is always a positive. I wanted to lock my card up, and once I did that I was going to go chase some tour starts."
Hadley has three Web.com Tour victories, also winning the Rex Hospital Open and Web.com Tour Championship in 2013. The former Georgia Tech player lost a playoff to Conrad Shindler this year in the Rex Hospital Open.
"It's been a long time since I've won," Hadley said. "Gosh, that's almost three years, and I've went to the bottom. Winning on tour and rookie of the year. You do this, do that and you start to spiral, lose your confidence and get negative. I've gone from the top to the bottom and it doesn't take long."
Hossler closed with a 64. Making his fourth tour start, the 22-year-old former University of Texas player birdied the final two holes for a back-nine 30.
"I played phenomenal," Hossler said. "Chesson obviously played outstanding and all credit to him. If you were to tell me I would shoot 22 under at the beginning of the week and not win, that's hard to believe. He played well."
He earned $64,800 to go through 36th to 17th on the money list with $140,378.
Adam Long also shot a 64 to finish third at 19 under.
Sam Ryder was fourth at 18 under after a 69.
Hadley eagled the par-5 11th, birdied 12, chipped in for par on 16, birdied 17 and two-putted for par on 18.
"You want to be leading by 100 and just cruise on in," Hadley said. "You look at the scoreboard and you see Beau is at 21 under. You can never take the foot off the pedal That's the thing out here."