Kevin Tway shot a 7-under-par round of 66 on Thursday to build a one-shot lead after the first round of the Tournament of Champions in Maui, Hawaii.
Tway won the season-opening Safeway Open in October for his first PGA Tour victory, which included a spot in the winners-only Tournament of Champions to kick off 2018. He carded five birdies in making the turn in 31 shots, and then rolled in two more birdies on the back nine to complete a bogey-free card in windy conditions on the par-73 Plantation Course at Kapalua Resort.
Defending champion Dustin Johnson and fellow Americans Justin Thomas and Gary Woodland are one shot back after shooting 67s on Thursday. Johnson was 4 under on the par-5s, with the only blemish on his scorecard a bogey on No. 6 after driving the ball into the thick native grass and having to chop the ball out.
Marc Leishman is alone in fifth place at 5-under. Another shot back is a group of players that includes fellow Australian Jason Day, Northern Ireland's Rory McIlroy -- who is playing the event for the first time -- and Americans Bryson DeChambeau, Andrew Landry, Patton Kizzire and Andrew Putnam.
DeChambeau was one of the stories of the day, choosing to take advantage of the new rule that allows players to keep the pin in the hole while on the putting surface. DeChambeau opted to on many holes.
Tway is the son of eight-time PGA Tour winner Bob Tway, and recalled the Plantation Course from helping his father prepare for the 2004 event. And he needed all the knowledge he could get after pulling out of Wednesday's pro-am after only a few holes due to an ear and sinus infection.
"When you're making a lot of birdies it makes everything better," Tway said after Thursday's round. "I was just trying to drink a lot of water. But I didn't think I was going to play that good, to be honest ... still a little dizzy.
"I hit the ball well, kept the ball in play, made a few putts, controlled my ball in the wind.
"It's windy where I'm from in Oklahoma so it's kind of like I was at home. Each shot's difficult so you're just focused on the trajectory and where I need to land it and where I need to miss it."
NOTES: World No. 1 Brooks Koepka, who finished last in the event last year, opened with a 3-over 76 and is in a tie for 30. ... Kevin Na withdrew before the start of Round 1 with a fractured bone in his right pinkie finger, leaving the field at 33 players. Na said he injured the finger last week and that the pain became too intense to continue playing. He qualified for the TOC by winning the Greenbrier last July and said he hopes to return in time for the Waste Management Phoenix Open. ... Tiger Woods, Justin Rose and Phil Mickelson qualified for the TOC but chose not to play. ... Johnson has now posted 16 rounds in the 60s in the event since 2013, five more than Jordan Spieth. He also leads active Tour members with 11 consecutive seasons with at least one victory.