Haotong Li is the unlikely leader at the PGA Championship in San Francisco.
The 25-year-old from China delivered a 5-under 65 at TPC Harding Park in Friday's second round, leaving him in first place at 8-under 132.
Six players, including two-time defending champion Brooks Koepka, are two strokes back at 6-under 134.
Koepka shot a 2-under 68 on Friday to end the day level with first-round co-leader Jason Day of Australia (69), Daniel Berger (67), England's Tommy Fleetwood (64) and Justin Rose (68), and France's Mike Lorenzo-Vera (68).
Lorenzo-Vera was alone in second place until he bogeyed his final hole of the day.
Li made five birdies, four of them on the front nine, during a bogey-free round that marked his second straight strong effort. He shot 3 under on Thursday.
Even Li, ranked 114th in the world, couldn't explain his back-to-back stellar rounds in just his third PGA Tour tournament of 2020.
"Well, I've got no expectation actually, because you know, last few months, stay at home doing nothing," Li said. "I just want to be out here, have fun.
"Still got two rounds left. Long way to go. Just want to play my best. If it happens, it happens."
Li was in lockdown in China due to the coronavirus pandemic and certainly doesn't consider himself in top form.
In fact, he missed the cut at the Memorial Tournament last month and tied for 75th last week at the WGC-FedEx St. Jude Invitational.
"I didn't even think I could play like this this week," Li said. "Especially ... had no confidence."
Fleetwood had seven birdies and one bogey while tying Cameron Champ for the best rounds of the event so far, 6-under 64.
Fleetwood said he is trying to rediscover his form. He missed the cut two weeks ago at the 3M Open outside of Minneapolis and tied for 35th last week in Memphis.
"You come back and the game doesn't feel as easy as it once did," Fleetwood told CBS. "Just rustiness. Tournament golf is hard. It doesn't matter how much golf you play with friends and family at home. When you come back (to the PGA Tour), the margin for error is really small."
Day and Brendon Todd were first-round co-leaders. Todd shot even-par 70 on Friday to remain 5 under, tied for eighth. Champ (64) and England's Paul Casey (67) are also at 5 under.
World No. 2 Jon Rahm of Spain shot 69 and is at 1-under 139, tied for 31st. No. 3 Rory McIlroy of Northern Ireland (69) and No. 4 Webb Simpson (68) also are at 1 under.
Tiger Woods made the cut at even par despite a 2-over 72 on Friday. He is tied for 44th.
Phil Mickelson (69) is at 1-over 141, as are Justin Thomas (70) and Jordan Spieth (68), all of making the cut on the number in a tie for 60th.
Rickie Fowler (69) wound up 2 over and missed the cut. Spain's Sergio Garcia (73) missed the cut at 6 over.
--Field Level Media