England's Paul Waring ripped up the form book to claim a shock early lead after the opening round of the PGA Tour's Texas Children's Houston Open.
The 41-year-old has fallen outside of the world's top 300 and has finished no higher than tied-27th since joining the PGA Tour at the start of the 2025, with Waring currently playing on a medical extension to his tour card after seeing last season cut short due to injury.
Waring birdied three of his first four holes on his way to a bogey-free 63 at Memorial Park Golf Course, seeing him set the clubhouse target on seven under and post his lowest career round on the PGA Tour.
Gary Woodland is one off the lead after a birdie-birdie finish to his six-under 64, with Sam Burns sharing third spot with fellow Americans Tom Hoge and Michael Brennan.
English duo Marco Penge and Matt Wallace are both within three of the lead after four-under 66s, while Cole Hammer is also in contention after posting a hole-in-one at the par-three 15th during a low-scoring opening day.
Waring - beginning on the back nine - made a close-range birdie at the 10th and responded to a missed opportunity on the par-three next by posting back-to-back gains from the 12th, then took advantage of the par-five 16th and added another at the 18th to race to the turn in 30.
He ended a run of pars by holing from 30 feet at the fifth and picked up another birdie at the next, then scrambled a par at the eighth after having to play his third shot from stood in a creek.
"I found a little bit of momentum coming forward in the last few weeks," Waring said. "I know missed cuts at Valspar [Championship] and Cognizant [Classic], but felt like my golf game was in a good spot.
"I gave too many shots away in the first few weeks, where this week was a lot tidier - no bogeys and holed a good amount of footage today."
Chris Gotterup - the highest-ranked player in the field - and defending champion Min Woo Lee are both five off the pace after carding opening-round 68s, while Shane Lowry is a further shot back after a final-hole birdie helped him to a one-under 69.
Brooks Koepka was two under after five holes of his opening round but stumbled with three double-bogeys in a four-hole stretch around the turn, with a five-over 75 leaving the five-time major champion in danger of missing the cut.
This week's event is the last chance for players to break into the top 50 and qualify - if not already exempt - for The Masters. The only other way to secure an invite would be to win this tournament or next week's Valero Texas Open.
Who will win the Texas Children's Houston Open? Watch throughout the week live on Your Site. Early live coverage continues Friday from 12.30pm on Your Site Golf, ahead of full coverage from 7pm.