Top-ranked Dustin Johnson birdied his way through Amen Corner and clung to a share of the lead with South Korea's Im Sung-jae in Friday's second round of the 84th Masters. Johnson, the 2016 US Open winner, started on Augusta National's back nine and made the turn on 8-under, level for the lead with Im, a 22-year-old trying to become the first debut Masters winner since 1979. Third-ranked Justin Thomas, who also started at the 10th hole, closed his first nine with four consecutive birdies but fell from a share of the lead with a double-bogey at the first. Johnson's three birdies on the famed three-hole stretch starting at 11 included an eight-foot putt at the par-3 12th and a four-footer at the par-5 13th to reach 10-under for a four-stroke edge.
But he followed with a three-putt bogey at 14 and sent his approach into the water to bogey the par-5 15th then parred his way to the turn.
Earlier, Johnson sank a five-foot birdie putt at the 18th to complete an opening-round 65 to share the 18-hole lead after storms forced a Friday-morning finish.
Following his lowest career Masters round and first without a bogey, Johnson was quickly back on the course for round two.
"To continue to play is definitely a nice advantage," Johnson said. "I'm on a good roll."
Johnson could become the first world number one to win the Masters since Tiger Woods in 2002.
Johnson was a runner-up in three of the past six majors, including a best-ever Masters effort last year.
The lanky 36-year-old American, who grew up only an hour's drive from Augusta, missed two planned Masters tuneups after testing positive for Covid-19 last month but was a runner-up last week in Houston in his tour return.
- McIlroy fightback -
Since the PGA Tour's Covid-19 break, Johnson won at Hartford, was second at the PGA Championship, won the Tour Championship and shared sixth at the US Open.
Thomas, the 2017 PGA Championship winner, rolled in birdie putts from four to eight feet to briefly join the leaders, but went left off the first tee, hit a tree and went over the green on his approach in a Friday the 13th nightmare.
Thomas finished a morning 68, having never shot better than a 73 in four prior Masters opening rounds.
Im birdied 12 and 13 and answered a bogey at 14 with a birdie at 15 to stay level with Johnson.
Fifth-ranked Rory McIlroy, seeking a green jacket to complete a career Grand Slam, birdied four of his first eight holes in the second round to revive his hope of a Masters victory.
After stumbling to an opening 75 to share 77th, the four-time major winner started off the 10th with a birdie, curled in a 10-footer to birdie the par-3 12th, sank an eight-foot putt to birdie the par-5 15th and made a 15-foot birdie putt at the 17th to reach 1-under, the projected cut.
Rain-softened Augusta National surrendered the lowest opening-round scoring average in Masters history, 71.43 strokes.
There were a 53 players under par in round one and 24 scores in the 60s, both records for any round in Masters history. The old mark for sub-par players was 47 in round two in 1992.
Defending champion Woods awaited a late tee time after opening on 68, the 15-time major winner and five-time Masters champion matching his best-ever Augusta National start.
It was his first bogey-free Masters round since 2008 and in any major since 2009.
Germany's 63-year-old Bernhard Langer, a two-time Masters champion, opened on 68. With 62-year-old 1987 Masters winner Larry Mize opening on 70, it was the first round in major golf history where two players over 60 broke par.
The Masters was postponed from its usual April date by the Covid-19 pandemic, which also forced a ban on spectators as a safety precaution.