English teenager Kris Kim hit a three-under-par 68 on his PGA Tour debut as compatriot Matt Wallace took a one-shot lead at the CJ Cup Byron Nelson.
Kim, 16, holed five birdies and an eagle as he finished tied 53rd after the first round in McKinney, Texas.
Should the amateur make the cut after round two, he would be the fifth-youngest player to do so at a PGA Tour event.
Kim said the conditions were “pretty easy” but he would “definitely take” his score given it was his debut.
Wallace, 34, shot an eight-under 63, giving him a one-stroke lead from a pack of seven players.
The Englishman, who has missed the cut five times and doesn’t have a top-ten finish in 11 tournaments this year, says he is trying to learn from watching some of his younger rivals.
“What I’m seeing from a lot of them, especially the younger guys, younger than me – I’m not too old, but younger than me – they’re so focused in their shot and not worrying about the outcome or what’s out there,” said Wallace.
Play had to be suspended towards the end of the first round because of darkness, leaving nine players yet to finish.
Jason Day, the defending champion, finished three back after dropping two shots in his final five holes.
Jordan Spieth, a runner-up at the tournament in 2022, birdied three of his first five holes but faded down the back nine to finish three under.