Austrian Sepp Straka soared with an eagle and five birdies on Thursday to join a four-way tie for the lead on seven-under 65 in the PGA Tour's Corales Puntacana Championship.
Tyler McCumber had six birdies and an eagle and got as low as eight-under on the picturesque par-72 course, but a bogey at his penultimate hole, the eighth, dropped him back into a share of the first-round lead.
He and Straka were joined by Scott Harrington and Hudson Swafford, with China's Zhang Xinjun and American Joseph Bramlett a shot back on 66.
"Hitting the ball really well all day," Straka, seeking a first PGA Tour title, said of his round. "The couple of times I missed the green I got up and down, chipped in once, so, really just kind of everything was falling into place today."
Straka teed off on 10 and picked up four birdies in his first nine holes, the eagled the par-five fourth.
"Hit a pretty good drive in the fairway and had a good number for a five-wood in there," he said of his eagle. "Hit it about five feet and sunk the putt."
The course yielded 93 sub-par rounds, but Straka said it still demanded patience.
"You can shoot a low round out here, but it's got to be a consistent low round. You've got to let the birdies come to you.
"You're going to hit a lot of fairways, fairways are pretty wide," Straka added. "But you're going to want to hit your irons good because the greens, you can miss it in some bad spots."
Harrington said the island atmosphere made him more relaxed. He also has the confidence of knowing he shares the course record of 10-under 62, which he recorded in the second round of a Korn Ferry Tour event in 2016.
"I feel as kind of a longer player I can kind of let it rip a little bit," Harrington said.
Ten players were two off the pace on 67 and another dozen were tied on 68. That group included American Kelly Kraft, who stormed home with two eagles in his last three holes. That included a hole in one at his final hole, the ninth.
Defending champion Graeme McDowell, meanwhile, got off to a quiet start, firing a two-under par 70 that included three birdies and one bogey.
Leading first-round scores on Thursday in the PGA Tour Corales Puntacana Championship in the Dominican Republic (USA unless noted, par-72):
65 - Sepp Straka (AUT), Scott Harrington, Hudson Swafford, Tyler McCumber
66 - Zhang Xinjun (CHN), Joseph Bramlett
67 - Ricky Barnes, Cameron Percy (AUS), Justin Suh, David Hearn (CAN), Kyle Stanley, Sean O'Hair, Jamie Lovemark, Brian Stuard, Patrick Rodgers, Ryan Brehm
68 - Adam Schenk, Zac Blair, Nate Lashley, Mackenzie Hughes (CAN), Jonathan Byrd, James Hahn, Robert Streb, Thomas Detry (GER), Ben Martin, Denny McCarthy, Kelly Kraft, Mark Anderson