The Masters Tournament: Dustin Johnson, Jon Rahm and Justin Thomas in the mix

Leaders

All finished unless hole highlighted in parentheses

-9 Ancer, Smith, D Johnson, Thomas

-8 Im, Cantlay, Matsuyama (15), Rahm (12)

-7 Willett, Fleetwood, Rose, Pan (16), Oosthuizen (12)

Dustin Johnson and Justin Thomas were part of a four-way share of the clubhouse lead, but Jon Rahm will return to the course on Saturday with a five-foot birdie chance which, were he to hole it, would make it a five-way tie at the top.

The Spaniard is a narrow favourite with holes 14 to 18 still to play after he finishes the 13th, and could lead at the end of a round in a major championship for the first time in his career after reaching five-under through 12 on Friday evening.

Earlier, Johnson blew the tournament wide open with a stumbling end to a long day - but still did enough to keep a share of that clubhouse lead heading into the final two days.

With just half the field having completed their rounds following Thursday's rain delay, Johnson was tied with Justin Thomas, Abraham Ancer and Cameron Smith on nine-under, adding a two-under 70 to the stress-free 65 he completed in the morning.

But having reached 10-under after just four holes of his second round, Johnson passed up the opportunity to move into a clear lead and having touched 6/4 in-running, he looks set to enter the weekend no shorter than 4/1 with most bookmakers.

Johnson's troubles started with a three-putt at the 14th before he found water at the 15th, and he then made 11 pars in succession before finally taking a step back in the right direction with a birdie at the ninth.

Ancer made it a dream Masters debut with a second-round 67 to follow his maiden 68 and was joined first by Smith, his Presidents Cup team-mate and a contender here previously. The Australian, back to form of late, finished with an eagle at the 15th and then birdies at each of the final three holes to fly up the leaderboard.

And Thomas then completed the quartet when he too signed off with a birdie at the ninth, his seventh of the day in a remarkable round. The former PGA champion had been two-over early but was then two-under at the turn following birdies from the 15th to the 18th, before racking up a costly double-bogey at the first hole after hitting a tree with his second.

Thomas responded with a birdie at the second and two more to finish and could well play with Johnson in the third round, potentially in a penultimate pairing behind two who are seeking their major breakthroughs.

Patrick Cantlay and Sungjae Im are also finished and are both one behind, the former after a round of 66 which was matched by Danny Willett and Tommy Fleetwood, who form an English trio on seven-under along with Justin Rose. Phil Mickelson and Brooks Koepka are four back on five-under, while Rory McIlroy's slim Masters hopes were boosted in a second-round 66 which got him within six.

McIlroy will no doubt be pleased with his response to a clumsy 75 with which he began the event, and his task is now a stiff one with such quality atop the leaderboard.

"Out here you've got to take advantage of the par-fives - the first day I did, today I did not," said Johnson, who remains the man to beat. "Felt like I played really well, hit a lot of good shots, had a lot of good looks at birdie, but could not get the ball in the hole."

As the late starters went off in pursuit of the clubhouse scores, pre-tournament favourite Bryson DeChambeau was four-over through five holes before rallying to reach level par and get back inside the cut-line, but alongside him it was Rahm who made the most significant move.

The world number two fired wedges in close to the eighth and ninth holes to go out in four-under, and after a scrambled par at the 10th and a comfortable one at the 11th, a birdie at the iconic 12th hole saw him get within one of those who had finished hours earlier.

Another wedge in close to the 13th came just as the horn blew to suspend play, and Rahm declined the opportunity to attempt a slippery downhill birdie putt which is instead what he will return to face in the morning.

Tiger Woods was level through 10 holes and four-under for the tournament but Lee Westwood had fallen to two-under and outside the top 30 on a bunched leaderboard as light left the course at the end of a long day.

Shot of the day