Patrick Cantlay and Patrick Reed are tied for the lead after shooting 7-under-par 65s on Thursday in the first round of the Hero World Challenge in Nassau, Bahamas.
Tournament host Tiger Woods is eight back after carding a 1-over 73. Woods had four birdies on the day, but also had a pair of bogeys and a triple bogey on the par-3 12th hole.
"I didn't quite feel comfortable with my game today, even though I drove it great," Woods said. "It was definitely reflective in my scoring today. I didn't quite feel comfortable and just didn't quite hit the ball close enough or give myself a lot of looks at it."
The Hero World Challenge is not an official PGA Tour event but features a star-studded 18-player field.
Cantlay was the first to reach the clubhouse at 7 under. His bogey-free round included birdies on five of his final six holes. Reed did have one blemish on his scorecard with a bogey on No. 8 but led the field with eight birdies -- including four in posting a 32 on the back nine.
Cantlay gained a spot in the field earlier this month when Webb Simpson withdrew.
"I probably wouldn't be playing golf, but I'm glad I'm here," Cantlay said, according to Golfweek. "I knew I was on the edge (of making the Hero event) for a while, so I was hopeful that I would get in and fortunately I did."
Former No. 1 Dustin Johnson and Sweden's Henrik Stenson are tied for second at 4 under, three shots back of the leaders. Another stroke off the pace are Bubba Watson and Sweden's Alex Noren.
Defending champion Rickie Fowler is tied for 13th at even par. The only player behind Woods is Japan's Hideki Matsuyama, who struggled in an opening-round 2-over 74.
Woods, who took a lengthy layoff after the Ryder Cup in September, teed it up six days after losing the $9 million winner-take-all "The Match" against Phil Mickelson in Las Vegas.
Woods has won the Hero World Challenge a record five times.