Paul Casey seized the clubhouse lead in the darkness-halted opening round of the Masters on Thursday at rain-softened Augusta National while defending champion Tiger Woods showed the form to threaten for a 16th major title.
Casey, a 43-year-old Englishman chasing his first major title, fired a bogey-free seven-under par 65 -- matching his career-low from 218 major rounds.
"I've put a lot of work in to play this golf course and it has paid off," Casey said.
"It was a great round. I'm very happy with my 65."
Woods took full advantage of attackable conditions after three-quarters of an inch of rain and a storm delay of nearly three hours. He produced his first bogey-free Masters round since 2008 to share fourth in the clubhouse on 68.
"I did everything well today," Woods said. "The greens were soft. You have to seize your opportunities out there and take advantage."
Seventh-ranked Webb Simpson, the 2012 US Open champion, fired a 67 to share second with fellow American Xander Schauffele.
American Justin Thomas was also on five-under after 10 holes when sunset struck, leaving him among 44 players to finish their opening round Friday.
Japan's Hideki Matsuyama closed with back-to-back birdies to shoot 68 and share fourth with Woods, England's Lee Westwood, South Africa's Louis Oosthuizen and American Patrick Reed.
Casey, whose best start in 13 prior Masters appearances was a 69, was a runner-up at the PGA Championship in August for his best major finish.
"I've not played particularly great golf since this pandemic hit," Casey said. "I've been so excited to get here."
World number 22 Casey, whose other prior major 65 was in the last round of the 2018 Masters, opened with a birdie at the 10th hole, added more at the par-5 13th and 15th and another at the par-3 16th.
He eagled the par-5 second to seize the lead alone and stretched it with a birdie at the par-3 sixth then parred in, thrilled despite the lack of spectators due to Covid-19.
"There's this vibe, the aura that Augusta National has, something you can't measure that it's exciting to play on this golf course," Casey said.
Woods, who turns 45 next month, matched his best career Masters start from 2010 as he tries to match Jack Nicklaus with a record sixth green jacket -- and move two shy of Nicklaus's all-time major win mark.
"It's just experience," Woods said. "I just know how to play this golf course. There's a sense of ease when I come here, because I understand how to play here."
Woods, ranked 33rd, birdied the par-5 13th and 15th plus the par-3 16th and added another at the first hole.
"I put a lot of it together," Woods said. "It was good all around."
A win would give him 83 US PGA Tour titles, breaking the record he shares with Sam Snead.
US Open champion Bryson DeChambeau never approached the power-hitting success he enjoyed in overwhelming Winged Foot for his first major victory, closing with back-to-back birdies to settle for 70.
"Fortunate enough to be two-under," DeChambeau said. "It was a little risky out there. I'm OK with that. I just didn't execute some of my shots.
"Clearly today I didn't have my best stuff and I was still able to shoot under par."
Accuracy issues prevented DeChambeau from dominating, a double-bogey nightmare at the par-5 13th followed by birdies at 15 and 16.
- McIlroy, DJ to finish -
World number one Dustin Johnson and England's Justin Rose were both three-under through nine holes.
Four-time major winner Rory McIlroy, trying to complete a career Grand Slam with a Masters victory, was on level par through nine holes.
McIlroy would join Woods, Nicklaus, Gary Player, Ben Hogan and Gene Sarazen as the only career Slam winners with a victory.
Johnson is trying to win his second major title and become the first top-ranked player to win the Masters since Woods in 2002.
Westwood has 12 top-5 major finishes but no wins. The 47-year-old was a Masters runner-up in 2010 and 2016.