The 32-year-old American enjoyed a two-shot advantage after the opening round but he ended Friday (Saturday AEDT) as co-leader with three other players on 10-under par.

Stanley, looking for his third PGA Tour title, had four birdies and two bogeys in his second-round 70, which allowed compatriot Josh Teater, Argentinian Emiliano Grillo and Norwegian Viktor Hovland to close the gap.

Gibson followed up his opening day 66 with a second-round 70, meaning he sits two shots behind the leaders at eight-under.

Hovland, the 22-year-old from Oslo looking for his first PGA Tour title, had an eagle and five birdies in his six-under-par 66.

Grillo ended his second round with back-to-back birdies on the eighth and the ninth for a 68, the same score that Teater managed after an eagle, four birdies and two bogeys.

Sam Ryder produced a flawless round of 65 and lies one shot behind the leaders, while Gibson is tied with three others a further shot back.

There are 17 further players within four shots of the leaders as the tournament heads into the weekend.

Cameron Davis, John Senden (both four-under) and Cameron Percy (three-under) are the three remaining Australians in the field after Robert Allenby (three-over) missed the cut.

Australian Associated Press