Defending champion Justin Thomas racked up eight birdies in an eight-under par 65 on Thursday to share the first-round lead with Harris English in the US PGA Tour Tournament of Champions.

Thomas's five birdies on the front nine included three in a row at the seventh, eighth and ninth. He kept the round going with a spectacular par save at the 13th, where he hit into tall native grass, had to hunt for his ball and hit out to the fairway but drained a 37-foot putt.

He followed with birdies at 14 and 15 and birdied the last to join Harris in the clubhouse at eight-under, two strokes in front of a group of six players on 67 that included former Masters champions Sergio Garcia of Spain and Patrick Reed.

"It was a good day," Thomas said. "It was a good opening round. It was solid. I didn't do anything great, didn't do anything bad, just kind of made my way around the course."

He said the conditions, with less wind than expected on the par-73 Plantation course at Kapalua on the Hawaiian island of Maui, were "about as good as you could get them.

"Not much wind and soft greens, so I was glad to take advantage," Thomas said.

English's eight-under effort included a hole out for eagle at the ninth hole, along with seven birdies and one bogey.

"It was awesome," said English, who had three birdies in the first five holes.

"I got off to a really good start, making probably a 20-footer on No. 2, and that's what you've got to do out here."

"I felt like I was hitting the ball really well coming into it, and I feel like my iron game is probably one of my strengths," he said. "I think I only missed two or three greens out there today. I think I chipped one time, so a couple greens I did miss, I was still putting from the fringe.

"So just overall a really good ball-striking round and good putting round," English said.

Garcia erased two early bogeys with an eagle at the fifth. He added six birdies the rest of the way.

"Well, obviously didn't have the best of starts, just didn't hit a great shot on the first, three-putted and obviously just a little mistake on the green.

"Obviously the eagle was big to kind of get me back in the right frame of mind, and then I started to hit some good shots, roll in some good putts," added the Spaniard, who said he was unlucky not to come up with at least one birdie in the final few holes.

Reed grabbed his share of second with an eagle at the 18th. He and Garcia were joined on 67 by South Korea's Im Sung-jae, Canadian Nick Taylor and Americans Robert Streb and Ryan Palmer.

It was a further stroke back to Aussie Adam Scott and Americans Patrick Cantlay and Brendon Todd.

World number one Dustin Johnson, teeing it up for the first time since capturing his second major title at the pandemic-delayed Masters in November, had three birdies and a bogey in a two-under par 71.