Third-ranked Justin Thomas was set to challenge Amen Corner while top-ranked Dustin Johnson and Rory McIlroy sought a spark as the opening round of the 84th Masters resumed on Friday.
Thomas, the 2017 PGA Championship winner, was 5-under through 10 holes when darkness halted the storm-hit first round at Augusta National with 44 golfers yet to finish 18 holes.
England's Paul Casey owned the lead after a seven-under 65, matching his lowest-ever major round, with Americans Webb Simpson and Xander Schauffele in the clubhouse on 67 level with 27-year-old compatriot Thomas.
Never firing better than 73 in four prior Masters opening rounds, Thomas has improved his finish each year at Augusta National, reaching 12th last year, and looked set to charge again on a rain-softened layout.
Thomas opened with three birdies, added another at the fifth and answered a bogey at the seventh with birdies at the par-5 eighth and 10th to set a date with Amen Corner - the famed three-hole stretch starting at the 11th - just after dawn.
"I'm playing well. But it's not like I was sticking it really close or anything," Thomas said. "I'd love to continue the momentum.
"I've got a lot of golf left. It's a long day (Friday). I need to stay as patient as I possibly can."
Johnson and McIlroy, paired together, were looking for improved as they began the back nine, with PGA Player of the Year and Tour Championship winner Johnson on 3-under after nine thanks to an eagle at the par-5 second and birdie at the par-5 eighth.
"It was pretty good," Johnson said. "I hit some really nice shots, had some good looks. I'm pretty pleased how it went so far."
Johnson could become the first world number one to win the Masters since Tiger Woods in 2002.
McIlroy, on level par after his front nine after an opening bogey and a birdie at the eighth, would complete a career Grand Slam by winning the Masters, joining Woods, Jack Nicklaus, Ben Hogan, Gary Player and Gene Sarazen.
Defending champion Woods was in a pack sitting another stroke back after an opening 68, the 15-time major winner and five-time Masters champion matching his best-ever start at Augusta National.
It was his first bogey-free round at Augusta National since 2008 and in any major since 2009.
Woods, who turns 45 next month, could match the record six green jackets won by Jack Nicklaus and break the US PGA title record of 82 he shares with Sam Snead.
Australia's Adam Scott, the 2013 Masters champion, was on 4-under through 10 with South Africa's Dylan Frittelli 4-under after nine and American Matthew Wolff - the US Open runner-up after placing fourth at the PGA Championship in his major debut - at 4-under through 11 holes.