Jon Rahm shot a course record 61 as his bid for a fifth win of the year moved up a gear in the third round of the Mexico Open.
The Masters champion went out in 29 to move within two of leader Tony Finau.
Akshay Bhatia, playing in just his sixth PGA Tour event, will join the tournament’s big two names in the final group after equalling the previous Vidanta Vallarta course record of 63 to sit alongside Rahm on 17 under.
Rahm, who hit 17 greens in regulation, had the chance of a rare 59 but missed birdie putts on 15 and 16 before seeing his drive at the 18th plug in a fairway bunker as he had to settle for a par.
He said following his round: “It was a great round. The swings didn’t feel that different today to the first two days. The first two rounds, a couple of the not-so-good swings cost me a little bit too much
“Today, everything just seemed perfect. Made a lot of great swings and the ones that weren’t great, still gave myself a good result.”
The world number one needed just 25 putts as he equalled his career-low round.
“I think that’s the difference usually in a course like this,” he said. “To get to 10 under you’re going to have to make a few lengthy ones, and combined with really good ball-striking, great round. Really happy with what I did and just glad I gave myself a chance.”
Rahm, who is looking to defend a PGA title for the first time, could become the first player with five wins on the tour before May since Johnny Miller in 1974.
Finau, the only other member of the world’s top 20 in the field, birdied five of his last seven holes as he carded a 65 to maintain his lead heading into the final round.
Rahm, who beat him to the title 12 months ago, briefly edged ahead before the American’s strong finish.
Bhatia, 21, leapfrogged into the final group with an eagle on the last having played a practice round with Rahm and Finau earlier in the week.
Brandon Wu, who was second alongside Finau last year, is a shot further back and the only other person within five strokes of the lead.
Ben Taylor edged into the top 10 with a 66, two better than fellow Englishman Harry Hall.