South Korea's Tom Kim shoots 64 to share lead at weather-hit Charles Schwab Challenge

Kim is tied at the top with J.J. Spaun, Ryan Gerard, Andrew Putnam, Matt McCarty and Lee Hodges after the opening round at Colonial Country Club.

Before play was suspended, Kim caught fire with seven birdies in an eight-hole stretch from the 14th to the third, and despite mixing two bogeys with a birdie from the fifth to the seventh, he remained satisfied with his opening-round performance.

"Instead of thinking about the play or the finish," he said, "every day I'm trying to build on what I'm working on and putting all the pieces together where hopefully I can keep getting my game better where I feel comfortable and start competing at a high level consistently."

Putnam, who carded a bogey-free round, is chasing his second PGA Tour title and first since the 2018 Barracuda Championship, while Ryan Gerard - whose lone tour victory came at last year's Barracuda Championship - mixed eight birdies with two bogeys in his opening-round 64.

"Swinging it nicely, hitting it where I want to for the most part, and just it was nice to get a couple putts to go in," Gerard said. "I know the stats are probably going to lean more putting, but I've been hitting my driver really well and just like to continue doing what I'm doing for the rest of the week."

A group of 12 players sit one shot off the lead on five-under 65, including major winners Keegan Bradley, Brian Harman and Gary Woodland, as well as Alex Smalley, who is chasing his maiden PGA Tour title after holding the surprise 54-hole lead at the PGA Championship earlier this month.

Max Homa, Russell Henley and Japan's Hideki Matsuyama are another stroke back on four-under 66, while defending champion Ben Griffin opened with a two-under 68.