Jason Day has kept the Aussie form going on the US PGA Tour with a birdie and a clutch par save from the bunker on the final two holes to win the Arnold Palmer Invitational at Bay Hill on Monday (AEST).

The 28-year-old carded a 2-under par 70 for a one-shot triumph over Kevin Chappell, who looked to seal a maiden victory in his 150th career start but for a bogey on the 18th hole and a 69. Troy Merritt and Henrik Stenson both faltered late and tied for third.

Day, gunning for his for his eighth victory on tour, was one shot back and facing two of the hardest holes at Bay Hill. He hit his tee shot on the par-3 17th to 12 feet and made the birdie, and then got up-and-down from 30 metres away in a bunker to win by one shot. The US PGA Champion collected $US1.134 million ($1.49 million) and the win will elevate him from third to second on the Official World Golf Rankings.

Watch all the highlights below courtesy of the US PGA Tour: