WASHINGTON: Phil Mickelson, seeking to add to his haul of 44 US PGA Tour titles for the first time since 2019, fired a seven-under-par 64 on Thursday to grab a two-shot lead at Quail Hollow.

The five-time major winner, who has won two titles on the Champions tour since turning 50 last year, had eight birdies and a bogey over the par-71 layout in Charlotte, North Carolina, to lead South Korean Lee Kyoung-hoon and Keegan Bradley.

"The biggest thing for me was being able to stay present and focused on each shot, because my mind has been having a tendency to wander," Mickelson said.

"So I hit a lot of good shots and had a really fun day."

Mickelson said after missing the cut at the Valspar Championship last week that his inability to focus for an entire round, or refocus after a distraction, had become a problem as he got older.

But he said the demands of the "hard pars" at Quail Hollow -- where he has 10 top-10 finishes in 17 prior starts -- actually made it easier to concentrate.

A little levity added into the mix thanks to his back and forth with playing partner Joel Dahmen made for a good day that saw Mickelson open with a two-foot birdie at the 10th.

After his lone bogey of the day at 11, Mickelson got up and down for birdie from greenside bunkers at 14 and 15 and gave himself a five-footer for birdie to keep the run going at 16.

Back-to-back birdies at 18 and the first were followed by another brace at seven and eight.

Mickelson maintained his advantage with a par save at the ninth.

"There's nothing physically holding me back from playing at a high level, but you cannot make mistakes at this level," Mickelson said. "The guys out here are just so good, and I've been making a lot of errors, just simply not being mentally sharp."

Lee had set a target early, his 66 featuring birdie putts of 38 and 32 feet and an up and down for birdie from the greenside bunker at 15.