Min Woo Lee carded a 9-under 63 in the first round of the Rocket Classic on Thursday, tying a course record at the Detroit Golf Club.
Starting on the back nine, the 26-year-old Australian opened birdie-bogey, then rattled off nine birdies over the next 16 holes. He closed with three consecutive birdies to take the clubhouse lead in the early wave.
Lee has one PGA Tour win, which came in March at the Texas Children's Houston Open.
Andrew Putnam shot a 64 to put him one stroke back in the early group, followed by Lee Hodges and Zach Johnson, who were 7-under after rounds of 65.