Denny McCarthy rebounded from an early setback on Thursday to scorch the final 13 holes at Trinity Forest Golf Club and take a one-stroke lead after one round at the AT&T Byron Nelson in Dallas.
McCarthy leads Tyler Duncan and Tom Hoge by one stroke after shooting 8-under 63.
World No. 3 Brooks Koepka, the highest-ranked player in the field, is one of nine players tied for fourth place after shooting 65. Nine more are another stroke back at 5 under.
McCarthy, a 26-year-old fifth-year pro seeking his first PGA title, opened with three pars before double-bogeying the par-4 sixth, following a penalty off his tee shot. But he responded by starting an incredible run at No. 6, birdieing five straight holes, eight of nine and 10 of 12 to go 10 under across the final 13 holes.
On greens softened by rain, McCarthy attacked pins with deadly accuracy. All 10 birdie putts came from 18 feet or closer, and six game from within nine feet. He also drained an eight-footer for par at the 18th to cap a 6-under 29 on the back nine.
“I’m not the farthest hitter, so the golf course played somewhat long for me, but I really put some work in on my mid-irons, long irons, so gave me a chance to work on those today,” McCarthy told reporters afterward. “Hit a lot of great ones today.”
McCarthy, who has one Web.com Tour victory, has missed six cuts in 12 PGA Tour tournaments since late January, including last week at the Wells Fargo Championship. His only finish better than 26th this year came when he tied for ninth at the Valspar Championship in March.
“I’ve kind of been looking for a round like this just to kind of get me going,” he said. “I know I can be out here playing with the best, and today kind of showed that. It’s a good start but still have three more days to go.”
Duncan started on the back nine and also had a hot finish, playing his final nine holes at 6 under with the help of an eagle at the par-4 fifth. Hoge had a bogey-free day with seven birdies.
Koepka also started on the back nine and was 6 under through 14 holes before finishing bogey-birdie-birdie-bogey.
“I’m pleased with the way I played,” Koepka said afterward. “What I did there on 6 … just hit a flyer from the middle of the fairway, and 9, didn’t hit a good shot. Other than that, I struck the ball beautifully.”
Former Dallas Cowboys quarterback Tony Romo shot 5-over 76 and is tied for 148th in the 155-person field. He opened with a birdie and got as low as 2 under with an eagle at the par-5 seventh, but he double-bogeyed Nos. 9 and 13 before three bogeys in the final four holes.
Defending champion Aaron Wise is tied for 55th after shooting 69.
D.J. Trahan withdrew after eight holes.