Australia's Cameron Davis fired a seven-under par 64 to share the lead with Americans Harris English, Kevin Streelman and Russell Henley after Thursday's opening round of the US PGA Northern Trust.
Davis, chasing his first US PGA title, made eight birdies against a lone bogey on his penultimate hole to join the US pack atop the leaderboard in the FedEx Cup playoff opener at TPC Boston.
"My game suits this place pretty well," the 25-year-old from Sydney said. "We've got to hit our irons well. I felt like all I had to do was play a nice solid round of golf.
"I was able to get a few more putts to go in and that's nice to see. Nice to finally get a low one."
Davis opened and closed the back side, his opening nine holes, with back-to-back birdies on putts inside six feet and added a 12-foot birdie putt at 14.
The Aussie added 21-foot birdie putts at the par-5 second and par-4 sixth but found brush at the par-3 eighth and took a bogey.
"You just have to plot your way around," Davis said. "Being aggressive is just going to bring in bigger numbers."
The top 70 players in season points advance from Boston to next week's BMW Championship with only the top 30 going from there to the season-ending Tour Championship next month at East Lake.
English and Streelman are in the top 30 but Davis is 91st and Henley 10 more spots back, needing big weeks to advance.
Streelman had three sets of back-to-back birdies and holed out for eagle from 148 yards in the fairway at the par-4 15th.
"It was pretty fun," Streelman said. "I hit a 9-iron that was going right at the hole... I walked up and I didn't see the ball, said maybe it went in and I pulled the ball out."
Henley's bogey-free round saw him close with an eagle and two birdies in the last four holes. He birdied the par-4 15th and 17th from just over six feet then dropped his second shot at the par-5 18th only inches from the cup.
"It felt like the game came to me for sure," Henley said. "I was happy to finish that way."
English, who won his only two PGA titles in 2013 at the St. Jude Classic and the Mayakoba Classic, eagled the par-5 second from 97 yards in the fairway then birdied three and four.
English ran off four straight birdies starting at the par-3 11th and including a 41-foot putt at 13. he answered a bogey at 17 with a tap-in birdie at 18.
Streelman seeks his third career PGA victory after 2013 at Tampa Bay and the 2014 Travelers Championship.
Henley seeks a fourth after the 2013 Sony Open in Hawaii, the 2014 Honda Classic and 2017 Houston Open.
One stroke back on 65 were South Africa's Louis Oosthuizen, Colombia's Sebastian Munoz and Americans Charley Hoffman, Scott Piercy, Bubba Watson, Kevin Kisner and Matthew Wolff.
Reigning Masters champion Tiger Woods, returning to the Scotty Cameron putter he used in 14 of his 15 major triumphs, opened on 68.
"Just stubbornness I guess," Woods said of the switch back. "I'll put it in play and see how it goes and it worked. When I gave myself some chances I made them."
- Munoz birdies 7 in row -
Munoz birdied the first seven holes.
"I just saw the lines and made my putts," he said. "I didn't think about anything. It's great to be in the zone and I was there."
Two-time Masters champion Bubba Watson was working on mental issues.
"It comes down to thinking I'm man enough to hit the shots and then able to make the putts," Watson said.
"It's a lot more mental than people think. Life is hard."