Scotland's Martin Laird will take a three-shot lead into the final day of the Waste Management Phoenix Open on Sunday.
Laird, who led by two shots at the halfway stage, extended his advantage by a shot with a third-round three-under 68 to lie three clear of American duo Brooks Koepka and Zach Johnson and Japan's Hideki Matsuyama.
Spanish amateur Jon Rahm is one of three players a further shot back on nine under, while Laird's countryman Russell Knox and Bubba Watson are two of nine players five shots off the lead.
Laird's third round got off to a stuttering start when he bogeyed the par-four first hole, but after parring the second he birdied the third and fourth to move to 11 under overall.
Another bogey at the fifth hampered his progress but his third birdie on the ninth ensured a steady, if not spectacular, front nine.
Laird picked up further shots and the 11th and 13th holes to move to 13 under and, although he registered his third bogey of the round when he dropped a shot at the 15th, he atoned on the penultimate hole with his sixth birdie to restore his 13-under score.
Laird's topsy-turvy round was in stark contrast to his previous two rounds - he had only carded one bogey in his first 36 holes - and he conceded afterwards that he will have to raise his game in order to secure his fourth PGA Tour tournament victory on Sunday.
"Today was a little bit of everything," Laird told the PGA Tour website. "I hit some of my best shots and some of my worst.
Obviously, I'm happy to extend my lead. I'm going to have to play better tomorrow."
Matsuyama, meanwhile, recorded the best round of the day - an eight-under-par 63 - to remain firmly in contention with one round to play in Arizona.
The 22-year-old Japanese right-hander picked up three shots on the front nine and after another at the 13th to move to six under par, he picked up shots on each of the final four holes to close to within three shots of the lead.
Francesco Molinari is, along with Knox and Watson, another on eight under and the Italian got the 15,000-odd spectators at the 16th hole excited by carding an ace at the par-three hole, with the crowd responding by throwing their drinks onto the green in appreciation.
"Number 16 was just something really incredible," the Italian said afterwards. "It's my third hole-in-one in my life and the reaction was really special."