Justin Lower leads the Valero Texas Open through nine holes with play suspended due to darkness as Padraig Harrington and Matt Kuchar joined the group one stroke behind on Thursday.
The opening round was called off early in fading light, with play having been delayed numerous times in the morning due to fog in South Texas.
Lower, 33, got through the first half of his round, managing an eagle on the par-five 14th hole along with three birdies for a five under start.
Three-time major winner Padraig Harrington, 51, wound back the clock in his 333rd start in his 28th season. The Irishman, playing in familiar conditions, carded a four-under 68 with six birdies.
"What in the world is he doing?" @Padraig_H's creativity paid off @ValeroTXOpen. pic.twitter.com/UA6L058SVk— PGA TOUR (@PGATOUR) March 30, 2023
Fellow veteran Matt Kuchar had a similar round with six birdies and two bogeys for a four-under 68 to be tied for second.
The 44-year-old American and Harrington are alongside South Africa's M.J. Daffue, Mexico's Roberto Diaz and USA's Patrick Rodgers.
Fresh from winning last week's Corales Puntacana Championship, Matt Wallace is in a group of eight players, including Canada's Corey Conners (through nine holes), one stroke behind at three under overall.
Pre-tournament favourite Tyrrell Hatton only got through 10 holes to be two under, while Rickie Fowler and defending champion J.J Spaun were both even after 11 holes.
What a round from Matt Kuchar— PGA TOUR (@PGATOUR) March 30, 2023
He is tied for the lead in the clubhouse @ValeroTXOpen. pic.twitter.com/P0C0QYi1ol