FORT WORTH, Texas (AP) -- Masters champion Jordan Spieth made a 20-foot birdie putt with darkness falling for a 6-under 64 and a share of the first-round lead Thursday in the rain-delayed Colonial.
Spieth just missed the green on his approach at the 18th hole, and putted from off the back right fringe. The closing birdie shortly after 8 p.m. put him atop the leaderboard with Kevin Na, Boo Weekley and Ryo Ishikawa.
After missing the cut at The Players Championship two weeks ago, the 21-year-old Spieth is playing the first of consecutive weeks at home in North Texas.
Spieth opened his bogey-free round with a 25-foot birdie putt at No. 1, then started the back nine with another a 22-footer at No. 10. He had a great chance for another birdie on the par-3 16th, but his 4-foot try slid by the hole.
Ishikawa, the 23-year-old from Japan, and 2013 Colonial champion Weekley also were without a bogey.
Na, whose only bogey came at No. 18 to close his first nine, curled up in a corner of the locker room and took a nap when tee times for the morning groups like his were pushed back three hours after more than an inch of rain fell overnight at Hogan's Alley.
The afternoon groups started 2 hours, 40 minutes later than scheduled, but all 122 players managed to finish before dark.
George McNeill and Ian Poulter, who shared the lead before his only bogey at No. 18, were a shot back after shooting 65.
A group of nine players carded 66s on a day when players were able to lift, clean and place their golf balls hit in the fairways.
After the rain, it was an unseasonably cool with temperatures only getting into the mid-60s with an unusual North wind blowing through the traditional tree-lined course. The forecast is for warmer temperatures but more rain through the weekend.
Defending Colonial champion Adam Scott had a 72 that included three bogeys and a double bogey. He is No. 11 in the world and hasn't won since Colonial last year in his first week after becoming the top-ranked player.
Weekley, whose last PGA Tour win was Colonial, woke up with a stiff back Wednesday that was still bothering him when he finally teed off Thursday.
"Felt like we just punched it around the golf course," he said. "And I made some putts. Made a lot of putts actually."
His 27 putts were a collective distance of 151 feet, 9 inches, Weekley's fourth-best putting round on the PGA Tour. He made all 12 of his putts from inside 10 feet.