American Matthew Wolff fired a three-under par 68 and stretched his lead to three strokes after Friday's second round of the US PGA Mayakoba Championship in Mexico.
The 22-year-old runner-up at the 2020 US Open stood on 13-under 129 after 36 holes at El Camaleon, where he set a course record Thursday with a 61 to lead by two.
Wolff, who won his only US PGA title at the 2019 3M Open, contended again at this year's US Open and seized his first consecutive solo 18- and 36-hole leads in Mexico after a runner-up effort last month at Las Vegas.
"A lot of good," Wolff said. "I feel like I'm hitting it pretty good. All parts of my game are clicking.
"I'm ready for the weekend. I'm giving myself a lot of good looks from the middle of the fairway with not-so-long clubs."
A victory would put him in rare company as a double PGA winner before the age of 23, joining Tiger Woods, Phil Mickelson and Jordan Spieth.
"I put myself in a pretty good spot," Wolff said. "Pretty happy for the weekend."
American Scottie Scheffler, chasing his first US PGA triumph, fired a bogey-free 64 to stand second on 131. He started off the 10th tee and caught fire with a birdie run from the fourth through eighth holes.
"I gave myself a lot of looks," said Scheffler. "I don't think I missed very many greens. That's really important around this place, just keep it in position. I did a good job of that."
Norway's Viktor Hovland, the defending champion, and Mexico's Carlos Ortiz shared third on 132.
India's Anirban Lahiri, Spain's Sergio Garcia and Americans Bill Haas, Aaron Wise, Talor Gooch, Justin Thomas, Billy Horschel, Ryan Palmer, J.J. Spaun and Michael Thompson were on 133.
- 'Bad breaks' late -
Wolff started Friday with a birdie and followed with more at the par-4 third and par-5 fifth before taking his first bogey of the event at the par-4 sixth.
Wolff answered with a birdie at the par-4 seventh and birdied the par-3 10th and par-5 13th to stretch his lead to five shots.
But he found a greenside bunker at the par-4 16th and made bogey and missed a 15-foot par putt at 18, trimming his edge entering the weekend.
"I had a couple bad breaks coming in," he said. "It was a hard finish but I was really happy with how I played."
Hovland, who began off the 10th tee and made three back-nine birdies, found the rough, a sprinkler head and a penalty drop at the first hole on the way to a double bogey.
But he birdied three of the next four holes and added birdies at the par-5 seventh and par-4 ninth.
"I played really solid. It didn't feel like I did anything extravagant out there." Hovland said. "I just had to reset and I was happy I made five birdies coming in."
Ortiz, another back-nine starter, birdied the par-5 13th and par-3 15th before his lone bogey at 18, then reeled off four birdies in a row starting at the second and closed with a birdie at the ninth.
"The front-nine is pretty gettable. I took advantage of that," Ortiz said. "I kept grinding. It's a good course to bump it around and that's what I did."