Day matched the TPC Sawgrass course record with an opening-round 63 and followed with a 66 on the way to a 72-hole total of 15-under 273.

The 28-year-old Australian took his 10th career US PGA title and a top prize of $1.89 million (1.67 million euros) at the $10.5 million event. Day’s seventh win in 17 starts was also his fifth in a row when leading after 54 holes.

Chappell fired a 69 to finish second on 277, one stroke ahead of fellow Americans Justin Thomas, Ken Duke, Matt Kuchar and Colt Knost with Italy’s Francesco Molinari and Japan’s Hideki Matsuyama sharing seventh on 279.

It was the second start-to-finish triumph of the season for Day, who also led after every round in taking the Arnold Palmer Invitational at Bay Hill. Since 1980, only Tiger Woods had two wire-to-wire US PGA wins in the same year.

Day’s impressive victory run over the past 10 months includes his first major title at last August’s PGA Championship, the Barclays and BMW Championship in last year’s US PGA playoffs and this year’s World Golf Championships Match Play.

Day has top-10 finishes in the past four majors and will try to add to his major win total in next month’s US Open at Oakmont.

The victory made Day the third reigning world number one to capture the Players, joining Woods and Greg Norman, and the fourth Aussie to win the event after Norman, Adam Scott and Steve Elkington.

Third-ranked Rory McIlroy birdied the par-5 second, ninth and 11th holes to move within five of Day with six holes remaining, but he found the water at the par-3 13th, took another bogey at 15 and a closing birdie gave him a 70 to share 12th on 281.