Ryan Brehm drained a long eagle putt at the 18th to cap a five-under-par 67 and take one-shot lead in the US PGA Tour Puerto Rico Open on Friday.
Brehm, making his final start on a minor medical exemption, would earn full tour status for the remainder of the season if he can capture his first US PGA Tour title at Rio Grande.
Solo second would still give him limited playing privileges for the rest of the campaign.
"It would be wrong to say you don't think about it, but realistically, since the beginning of this year we've just been trying to improve every day, every week," said Brehm.
After birdies at the second and 12th holes, Brehm closed with a flourish with a birdie at 17 and his eagle at the par-five finishing hole.
That left him on 11-under 133 and one shot clear of overnight co-leader Michael Kim, who carded a 69, Japan's Satoshi Kodaira, who signed for a 66 and American Max McGreevy, who had four birdies on each side in an impressive eight-under 64.
"It was kind of boring until the end," Brehm said. "I feel like I had to scramble quite a bit, had some difficult up-and-downs, got them up and down, made a few good putts for par, kept the momentum going and finished with a birdie-eagle, made a bomb on the last hole. You add it up, it's pretty good."
The tournament is being played opposite the Arnold Palmer Invitational.
Among Brehm's closest pursuers, McGreevy is also chasing a maiden title. Kodaira and Kim are both seeking their second titles. Kodaira won the RBC Heritage in 2018, the same season Kim won the John Deere Classic.
SCORES:
133 - Ryan Brehm 66-67
134 - Michael Kim 65-69, Satoshi Kodaira (JPN) 68-66, Max McGreevy 70-64
135 - Callum Tarren (ENG) 70-65
136 - Tommy Gainey 69-67, Jim Knous 71-65, Andrew Novak 69-67, a-Christopher Gotterup 68-68, Bae Sang-moon (KOR) 69-67, Kiradech Aphibarnrat (THA) 67-69, Matthias Schwab (AUT) 70-66, Patrick Flavin 68-68