Canada's Nick Taylor was second with Spain's Jon Rahm a further three shots back.

"I'm just proud with how I fought, I didn't have my best stuff," Scheffler told CBS.

"I ground it out, I wasn't hitting it good off the tee, my irons weren't as sharp, but I played a great round of golf."

Scheffler replaces Rory McIlroy - who finished joint 32nd on four under - at the top of the world rankings, having previously held the number one spot for 30 weeks until October.

He started the final round with a two-stroke lead but saw that halved immediately as both Taylor and Rahm birdied the first.

Scheffler hit back with birdies on the second and third holes, while Rahm's challenge faded with a bogey at eight.

With six holes remaining, Taylor and Scheffler were tied for the lead before the American drained an eagle putt on the 13th to take outright control.

Scheffler then holed a 15-foot clutch putt on the par-three 16th to preserve his advantage before a comfortable par on the last sealed his fifth title on the PGA Tour, and his first since his win at Augusta in April.

He is the third player to successfully defend a PGA Tour title this season after McIlroy at the CJ Cup and Max Homa at the Fortinet Championship.