Adam Hadwin has carded a third-round 59 to take over from Hudson Swafford at the top of the CareerBuilder Challenge standings in California.
The 29-year-old becomes the second player to shoot 59 on the PGA Tour this year, following on from Justin Thomas at the Sony Open, and the fourth in history to achieve it on a par-72 course.
Hadwin's incredible third-round score, which included 13 birdies and no shots dropped, saw him jump up the leaderboard heading into Sunday's final session, with Dominic Bozzelli a stroke behind.
Seven others could also mount a charge from the chasing pack, as Hadwin - without a win on the PGA Tour in his career - is just four shots ahead of Chris Kirk and Robert Garrigus who both occupy a share of eighth place.
Among those in hot pursuit is Swafford, who led overnight but failed to build on his seven-under-par 65 from the opening two rounds, slipping down to third in the standings with a score of 71.
