Kyle Stanley is on the verge of his first US Tour victory, holding a five-shot lead ahead of the final round of the Farmers Insurance.
The 24-year-old carded a third round 68, which included five birdies and one bogey, to leave him on 18-under-par with only 18 holes left to play at Torrey Pines.
Stanley, playing in the tournament for the first time, has impressed many this week and his three-round total of 198 has tied Tiger Woods for the 54-hole record at the course.
The man from Washington stated: "I've never had a third-round lead - especially one this big. I'm real happy with where I'm at, but I still have to go out there tomorrow and just keep playing golf."
Rookie John Huh and three-time Tour champion John Rollins are the closest challengers, tied for second on -13, with Korea's Sang-Moon Bae and Bill Haas a further shot back on -12.