Ryan Palmer birdied six of the last seven holes to share the lead with fellow American Harris English after Saturday's third round of the US PGA Tournament of Champions.
Palmer fired a bogey-free nine-under-par 64 to match English, who shot a bogey-free 66, on 21-under 198 after 54 holes over the par-73 Plantation course at Kapalua, Hawaii.
"It was pretty spot on," Palmer said of his round. "I drove it pretty well. My putting has really come around."
English hasn't made a bogey since the seventh hole of the opening round.
"Extremely satisfied," English said. "Normally Saturday is my toughest day. I feel like I played really well, stuck to my strategy, stayed patient.
"I'm confident about my game. I felt like I struck it really well."
Seventh-ranked Collin Morikawa, last year's PGA Championship winner, was third on 199 with fellow American Daniel Berger fourth on 201 and South Korea's Im Sung-jae and third-ranked Justin Thomas sharing fifth on 202.
Palmer has not won a solo PGA event since the 2010 Sony Open in Hawaii and English has not won a solo PGA event since 2013 at Mayakoba.
But both qualified for the Champions event by making the Tour Championship field last year in a special one-year entry rule change due to the Covid-19 pandemic.
A back-nine birdie barrage by the leaders set up Sunday's shootout for the crown in the first event of 2021.
English birdied the par-4 third from just inside 12 feet, sank a seven-foot putt to birdie the par-5 fifth, and added another birdie putt from just inside 30 feet at the par-3 eighth to reach 17-under.
English dropped his tee shot just beyond 17 feet and made the birdie putt at the par-3 11th to stretch his lead to three strokes.
Palmer made 12-foot birdie putts at the first and seventh holes around another at the par-5 fifth but then reeled off five birdies in a row from the 12th through 16th holes, four from inside six feet and the last from just over seven.
Morikawa and Palmer matched English for the lead time and again but he answered the challenge each time to retake the edge.
At the par-4 14th, he found a greenside bunker off the tee, pitched out to 17 feet, and sank the birdie putt. At the par-5 15th, English dropped his third just outside two feet from the cup and tapped in.
Palmer jumped ahead again at 16 but English sank a nine-foot birdie putt of his own at 16 to retake the lead at 21-under.
At the par-5 18th, Palmer reached the green in two and tapped in for birdie to equal English again.
No penalty for Palmer
English had to scramble at 18 when his second shot went into deep greenside rough. He blasted out and curled in a tense eight-foot par putt to keep his share of the lead.
"Just pulled it a little bit and got it going too far with the wind," said English. "Got a decent lie and was able to put a club on it. Was able to get out of there with a par. Pretty lucky there."
Palmer was lucky as well. After the round, he was questioned by officials about his actions at the ninth hole, where he botched a chip and kicked a divot while his ball was still rolling nearby. The ball wasn't on an angle to hit the divot and stopped without coming near it.
No penalty was imposed but Palmer was happy to still share the lead.
"I did the old kick a divot," Palmer said. "The ball stopped five feet away from me. The ball wasn't going to stop anywhere close to where I was.
"There was no way of me improving my lie whatsoever. There's no way I'm ever going to try to cheat the game."