Taylor Moore fires 62 to edge Brooks Koepka and Jesper Svensson at Byron Nelson

The native Texan, whose only PGA Tour triumph came at the 2023 Valspar Championship, made a blistering start after teeing off on the 10th at TPC Craig Ranch in McKinney, Texas. 

Moore collected four birdies on his opening nine before adding another five on the way home, including a decisive 14-foot birdie putt at the par-five ninth to claim the outright lead.

"Obviously pretty stoked," Moore said, adding that his distance control into the greens was key.

"I was really pleased with the iron shots I hit," he said.

Koepka, meanwhile, enjoyed an encouraging return to form as a switch in putters helped the five-time major champion fire an eight-under 63 - his best round since rejoining the PGA Tour this season following his stint with the LIV Golf circuit.

"Finally, I felt good with the putter," said the American, who had an eagle and six birdies.

"Just happy with the way everything went today," Koepka said.

Although Koepka returned to the PGA Tour with limited playing status, victory this week would secure him a place in the final two signature events of the season.

"It would be fantastic," Koepka said. "I feel like I'm knocking on the door, and I'm very, very close. I would love to have a chance on Sunday."

Sweden’s Jesper Svensson matched Koepka on eight-under after producing a round featuring nine birdies and a lone bogey.

Scoring was low across the board, with South Korea’s Si-woo Kim - a local resident - leading a pack of seven players on seven-under 64 after piling up eight birdies.

World number one Scottie Scheffler, the defending champion, opened with a five-under 66 to sit within striking distance alongside another large group of contenders.

"I did some good stuff," Scheffler said. "It's just a matter of getting closer and holing a few more putts."