Top-ranked Dustin Johnson seized command of the Masters on Saturday, matching the 54-hole record at Augusta National to grab a four-stroke lead in quest of a second major title.

Pulling away from an elite field at Augusta National, the 36-year-old American, who grew up only an hour's drive from the course, fired a seven-under-par 65 to stand on 16-under-par 200 after three rounds.

"I've got a lot of confidence in everything I'm doing," Johnson said. "Tomorrow I'm going to have to go out and do the same kind of thing.

"I've got a lot of of great players around me. I'm going to have to play a really good round if I want to put on that green jacket."

Johnson went a career major best four-under in the first four holes, making a tap-in eagle at the par-5 second, curling in a six-footer for birdie at the third and sinking a long birdie putt at the fourth.

He added tap-in birdies at the par-4 seventh, par-5 13th and par-5 15th to equal the 54-hole mark set in 2015 by Jordan Speith.

"It's really tough to read these greens," Johnson said. "You get a lot of putts that break a lot. We're reading them really well. Definitely pleased with the putting through three rounds."

Johnson is the first player to shoot 65 or better twice in the same Masters after a first-round 65.

Four-way chase

Im Sung-jae, a 22-year-old South Korean who could become the first debut Masters winner since 1979, closed with a birdie to shoot 68 and share second on 204 with Mexico's Abraham Ancer, another Augusta newcomer, and Australia's Cameron Smith.

"I played my first practice round Monday. I felt immediately the course suits my game and I thought I would do a good job," Im said through a translator.

"I really feel I will stay composed. My putting has been really good the past three days and I will just keep doing what I've been doing."

Im could become only the second Asian man to win a major after South Korean Yang Yong-eun at the 2009 PGA Championship.

Johnson, the 2016 US Open champion, is trying to become the first top-ranked golfer to win the Masters since Tiger Woods in 2002.

Defending champion Woods, who began four strokes off the pace, battled through back pain to shoot 72 and stand on 211, answering bogeys at the par-5 eighth and par-4 11th with birdies at the par-3 12th and par-5 15th.

"Long days like this, I'm going to get a little bit sore," Woods said. "I can walk all day. The hard part is bending and twisting."

Woods, a 15-time major winner who turns 45 next month, seeks a sixth green jacket and an 83rd career PGA Tour victory to break the record he shares with Sam Snead.

McIlroy fades

Nine golfers shared the lead at one stage as Augusta National's notorious undulating greens dried and quickened.

Smith, who closed with an eagle and three birdies to grab a share of the 36-hole lead, birdied 13, 14 and 15 to share second with Im and Ancer, who birdied 15 and 16 in a late charge.

South Africa's 100th-ranked Dylan Frittelli shot a bogey-free 67 with birdies on all four par-5 holes to stand fifth on 205.

"The putting is the big difference," he said. "I feel pretty comfortable out there on the greens."

Another stroke adrift was third-ranked American Justin Thomas, who settled for 71 after a closing bogey.

Second-ranked Jon Rahm shared seventh on 207 with Colombia's Sebastian Munoz and 2018 Masters winner Patrick Reed.

Spaniard Rahm suffered a double-bogey disaster at the eighth, rallied with birdies on 14 and 15 but stumbled with a closing bogey.

Fifth-ranked Rory McIlroy, needing only a green jacket to complete a career Grand Slam, shot 67 to stand on 208, but sees little hope of swiping the green jacket.

"Being a realist here, I just need to go out and shoot a good one tomorrow and see where it puts me," McIlroy said. "But I have zero thoughts about winning this golf tournament right now."

US Open winner Bryson DeChambeau, who many feared would overwhelm Augusta National with his power-driving game, tested negative for Covid-19 Friday after feeling dizzy on the course. He shot 69 Saturday to stand on 213.