Mitchell fires PGA career-low 61 to grab Truist lead
The 33-year-old American, who hasn't won a PGA event in more than six years, fired nine birdies, including on four of his last five holes, in a bogey-free start at Philadelphia Cricket Club.
"Everything kind of has to go your way to do that," Mitchell said of firing a career-low round. "I'm blessed that it did. I played great and hopefully I've got three more rounds to keep it going."
The event was moved from its usual home at Quail Hollow in Charlotte, North Carolina, because that course is hosting next week's 107th PGA Championship.
American Denny McCarthy was second on 62 with countrymen Rickie Fowler, Akshay Bhatia and Collin Morikawa, a two-time major winner, and Austrian Sepp Straka on 63.
"I'm pretty proud of how I played, just stayed true to playing solid golf out there," Morikawa said.
Defending champion Rory McIlroy shared 25th after an opening 66.
World number 90 Mitchell, who won his only PGA title at the 2019 Honda Classic, shared second last month at Puntacana and has opened on 64 in his prior three events, crediting patience grudgingly.
"I hate saying that. It's such an over-used word in golf," he said. "Golf makes you so impatient. You want everything right now, this shot, this putt, this drive. It's all the most important shot."
Mitchell, who started on the 10th hole, tapped in for birdie at the par-five 15th hole, then reeled off three birdies in a row with an eight-foot putt at 17, an 11-footer at 18 and a seven-footer at the first.
He sank a birdie putt from just inside 11 feet at the par-three third then ran off four birdies in a row starting with a tap-in at the par-five fifth followed by a five-footer at six, a tap-in at seven and a seven-footer at the eighth before a closing par.
'A great prep week'
McIlroy, in his first solo event since winning the Masters to complete the career Grand Slam, made a solid start in his last tuneup before next week's PGA at Quail Hollow, where he has won four times.
"This was always going to be a great prep week for me to see where my game was and sort of refine a few things," McIlroy said.
"I still want to play well and I still want to have a chance to win the tournament, but I'll have a really much better gauge of where my game is going into next week after these four days than I would've had if I hadn't had played or if I just spent the week at home practicing. So it's an important week for me."
Second-ranked McIlroy birdied three of the first six holes, including birdie putts from 12 and 16 feet, and added a 15-foot birdie putt at the 10th. He followed a three-putt bogey at 11 with an 18-foot birdie putt at the par-three 14th. After needing two to escape greenside rough to make bogey at the par-five 15th, he sank a nine-foot birdie putt at 17.
"Overall a decent day," McIlroy said. "I played pretty good. I felt like I was a little rusty out there, just hadn't played in a week and hadn't really done a ton of practice."