Patrick Reed and Carlos Ortiz will take a share of the lead into the final round of the Farmers Insurance Open.
Ortiz produced the best round of the day on the South Course at Torrey Pines on Saturday as the Mexican carded a six-under 66.
He was two under through 12 holes in his third round before producing a blistering finish, which included four birdies on his final six holes.
Ortiz moved into 10 under to share a two-stroke lead with Reed, who managed a 70.
Reed endured a rollercoaster round with an eagle and three birdies on the front nine, but he needed a bridie at the last to share the lead after four bogeys between 11 and 16.
The American was involved in some controversy at the 10th hole, where he sought relief for an embedded ball that replays showed had first bounced, and the 2018 Masters champion picked it up before the rules official arrived.
The full exchange as Patrick Reed takes embedded ball relief on No. 10. pic.twitter.com/gSPH6PrAoW— PGA TOUR (@PGATOUR) January 30, 2021
Asked if in hindsight he would pick the ball up before the rules official was there, Reed told CBS: "Yes.
"Because you sit there and when you have three players, including yourself, three caddies and a volunteer that's within five yards of that golf ball and no-one says it bounced, you're going to mark it and check to see if the ball is embedded. That's what every player does.
"If no-one sees it bounce, they see that it looks like it's broken the plain in the ground, you mark the ball and you pick it up first and then when you see that it is embedded that's when you always call the rules official over, no matter what you're doing, to take the drop to make sure you're doing the drop correctly."
Jon Rahm is one of five players tied for third at eight under after the Spaniard carded an even-par 72 in the third round.
Alongside Rahm are Sam Burns (70), Lanto Griffin (72), overnight leader Viktor Hovland (73) and Adam Scott (72).
Rory McIlroy remains in contention after shooting a 70 that sees him sitting alongside Sam Ryder (69), Will Zalatoris (70) and Ryan Palmer (73) at seven under.