A jubilant Kim Si-woo aced the 16th hole to push his lead to four strokes after the second round of the Texas Open at San Antonio on Friday.
South Korean Kim - who became the youngest victor of the Players Championship in 2017 - carded a three-under-par 69 on Saturday.
Rickie Fowler and Jordan Spieth, among only a handful of the big names using the Texas Open to tune-up for the Masters, both shot 68 on an unusually benign day in a typically windy location.
With Sunday's final round delayed by almost two hours after heavy rain deluged the course, Conners quickly moved to the top of the leaderboard with four birdies in his opening five holes to eclipse overnight leader Kim Si-woo who struggled to get going.
Also at 4 under after 68s are Morgan Hoffmann, Danny Lee, Ryan Moore, Ted Potter Jr., Scott Stallings and Chris Stroud.
"Besides having a fever last night, and dealing with allergies right now, I mean, withdrawing crossed my mind last night", Vegas said.
It was a wild round for Conners, a Canadian who had not won on any of the PGA Tour's affiliated circuits - he had finishes of second and third earlier this season.
"I told myself I could do it", Conners said.More news: Nipsey Hussle reportedly talked back to alleged killer during shooting
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Matt Kuchar is one shot back of Spieth and Fowler at three under while Jim Furyk is at two under. "The back nine today was by far the best I've played, the most control I've had of the ball and the best I've felt putting in a couple of years".
"I haven't really thought too much about it, but I'm really excited to get back there", he said. I made those adjustments mid-round and was able to shoot 5 under.
It's Kim's fourth appearance in this event. He hasn't had a top-10 finish since the same event a year later, when he tied for ninth place. Conners' seven-day ascent is the stuff players dream about, as he'll head quickly toward Magnolia Lane after becoming the latest player to win his way into the Masters at the very last moment. But on his 17th hole of the day, his tee shot on the par-5 went right of the fairway. That approach went in the bunker and he bogeyed.
The eagle came after Fowler's drive had carried 328 yards to within four feet of the hole.
Fowler has not played on Tour since he was tied for 47th at the Players.
Kim flirted with the 16th hole on the second bounce on Saturday.
However, Spieth has been out-of-sorts this year, so he was in an upbeat mood after his round.
Jordan Spieth is looking for his first victory since the 2017 British Open.