He holed a 12-foot birdie putt on the toughest pin position at the 18th - front and right - to end the day where he started.
American Gary Woodland, and clearly benefitting from a decision to commence working with putting expert, Phil Kenyon, continues to lead the "winners-only" event finding the "side door" for birdie at the 18th hole and this after brilliantly eagling the par-5 15th hole in an eventual round of 68 for a three-shot lead at 17-under par.
"I played great", said Woodland, "I would have liked to see a couple of putts go in early".
"Well it means I get to come back, which is even better", Schauffele said of qualifying for next year's Tournament of Champions with the victory.
Despite opening with a bogey, Schauffele quickly recovered, firing eight birdies and two eagles on his way to victory.
He got up and down for birdie from the left rough at the 14th, but wouldn't find another birdie the rest of the way in his second straight 68 for 205. "I didn't take too long of a look, but I just sort of got a quick feel of where I was", he said.
The only downer for Woodland was learning that his grandmother in Kansas had died Friday night.
"I want to send a little shout out to my family back home", he said. That put things in perspective real quick.
It was a tough day of work on the course, as the trade wind returned stronger than expected.
They were tied with three holes to play, with Schauffele in the group ahead of Woodland.
"I knew it was going to be a scramble from then on, so just kept my head down and made a run for it. I have a little different mindset this week, playing a little more aggressive, trying to contend and win instead of just enjoying the views out here, which I've done in the past".
His par left Woodland in solo second, and marked the seventh time he has failed to convert a 54-hole lead or share of the lead into a victory on the PGA Tour. Not known as a strong front-runner, Woodland said there's no reason he can't turn that around on Sunday.
"Today was really positive with the way I hit it; I drove it nicely and hit a lot of quality iron shots".
Rory McIlroy once again struggled in the final group on Sunday.
The Northern Irishman has always hit his driver high but a year ago realized he needed a shot off the tee that he could rely on when he simply had to get his golf ball into the fairway.
"So to get myself right back in contention and see if I've learned anything from past year and try to put that into practice is great". That gives him a two-shot lead over McIlroy, who is 14 under after a 5-under 68.
Rookie Cameron Champ (68) and Xander Schauffele (67) are keeping Thomas company at seven under, five adrift of Woodland.