SAN FRANCISCO (AFP) — Danny Willett, seeking his first US victory since the 2016 Masters, fired a bogey-free eight-under par 64 Friday to join defending champion Max Homa atop the leaderboard in the PGA Tour season opener.

England's Willett, whose eight DP World Tour titles include the Alfred Dunhill Links Championship last October, had eight birdies and was delighted to tour the Silverado Resort & Spa course without a bogey for the second straight day.

"Bogey-free is probably the most impressive," he said after joining Homa on 12-under par 132."

"We've not hit it amazing, we've hit it really good and this place still kind of jumps up.

"The rough is hit and miss and with the greens being firm as they are to go bogey-free is really good."

Willett got things going with a 26-foot birdie putt at the second hole. He left himself less than four feet for birdie at the sixth, drained a nine-footer at the eighth and a three-footer at the ninth.