"I was thinking 4, 5-under a day would be nice. You always get one or two guys that kind of go really low and I just happened to be that guy," Piercy said. Adam Hadwin and Hideki Matsuyama are each two shots back after a 7-under 64 at the TPC Twin Cities.
Seeking his fifth career tour win and first since the 2018 Zurich Classic, Piercy birdied one of his first seven holes and eight of his final 11, including a nearly 30-foot putt on No. 16 to get to 8 under. He needed just 25 strokes on the greens.
Piercy struggled late at the U.S. Open three weeks ago, including a final-round 77, and finished 52nd, but some rest and a tweak to how his driver is weighted produced a satisfying result. "I put in a few hours Friday, Saturday just to kind of get the rust off," he said.
He hit 13 of 14 fairways and 15 of 18 greens in a round that was interrupted early by a 36-minute weather delay and showers fell briefly a couple of times during the rest of his round. The winds also picked up at times in the afternoon.
Playing in the calm morning, Matsuyama and Hadwin found success on the soft greens. Ranked 93rd on tour, averaging 28.95 putts per round, Matsuyama had 26, including making 13 of 14 from inside 10 feet and four of five from 10 to 15 feet. He did not three-putt a hole.
"I've been trying lots of different things and the stance, the narrow stance, seemed to work today," he said through an interpreter. Starting on No. 10, Matsuyama, a five-time tour champion who last won at the 2017 Bridgestone Invitational, had four straight birdies around the turn before back-to-back birdies on Nos. 5 and 6. His lone bogey was his final hole.
Playing two groups behind Matsuyama, Hadwin was 3 under through nine holes, and birdied four straight holes among his final nine. "You prepare for a round like today and you've just got to be ready when it comes," Hadwin said.
He made all 15 putts from inside 10 feet and made two of three from between 20 and 25 feet. "I had those looks, my speed control was awesome all day and putts went in," he said. The 3M Open is the first regular tour event in Minnesota since 1969; however, the U.S. Open and PGA Championship have each twice been contested at Hazeltine National Golf Club. The 2016 Ryder Cup was also played there and is to return in 2028.
The tournament replaces a PGA Tour Champions event held in the Land of 10,000 Lakes for 26 years. "It's a great day for Minnesota golf, for sure," said Tom Lehman, who grew up in the state and helped lead the course renovation.
Arjun Atwal, Brian Harman, Sungjae Im, Patton Kizzire and Sam Saunders are three back after shooting 6-under 65. Brooks Koepka, the world's top-ranked player, is among more than a dozen players that shot a 4-under 67. Nate Lashley, who won last week's Rocket Mortgage Classic in Detroit, finished 2 under.
Phil Mickelson had seven penalty strokes, including two on the par-5 18th, and finished 3 over. Minnesota native Tim Herron aced the 208-yard eighth hole.
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