Brandt Snedeker is in the driver's seat in his quest to retain his Farmers Insurance Open title but the defending champion has company.
Snedeker carded a two-under-par 70 to move top of the leaderboard following the third round on Saturday.
However, fellow American Patrick Rodgers posted a bogey-free five-under-par 67 to move level alongside his countryman at nine under through 54 holes.
Snedeker and Rodgers are a stroke clear with one round remaining at Torrey Pines.
One shot off the lead when he teed off, Snedeker looked sharp early, birdieing two of his first three holes, but his round stalled after that, and it took a birdie on the par-four 17th to grab a share of the lead.
124 yards 1 foot-- PGA TOUR (@PGATOUR) January 28, 2017
154 yards 5 feet
144 yards 3 feet pic.twitter.com/0eyUznw3KT
Snedeker - a two-time winner at this event - won in dramatic fashion last year after posting a three-under 69 in terrible conditions, but he has never successfully defended a title on the PGA Tour.
Seeking a maiden Tour crown, Rodgers was flawless as he birdied the sixth, seventh, ninth, 10th and 13th holes.
Tony Finau (67) and Cheng Tsung Pan (69) are within striking distance.
Olympic gold medallist and overnight leader Justin Rose, meanwhile, ended the round two strokes off the pace.
After starting the penultimate round in the lead, Rose struggled as he shot a one-over-par 73 to fall back to seven under, alongside the likes of Marc Leishman (68), Stewart Cink (69), Jonas Blixt (69) and Harris English (69).
Phil Mickelson worked his way back into contention with a 68 to get to five under.