GULLANE, United Kingdom (AFP) ― Zach Johnson used a red-hot putter to lead the British Open at scorching Muirfield on Thursday on a pulsating opening day when some of the biggest names in the game were left reeling.

The 2007 Masters champion fired an eagle at the par-five fifth and used that as the springboard toward a five under 66 that held firm throughout the day.

Indian qualifier Shiv Kapur briefly threatened to dislodge him from atop the leaderboard as he went six under after just seven holes.

But he dropped shots down the back nine and had to settle for a 68, level with Miguel Angel Jimenez of Spain and Americans Dustin Johnson, Brandt Snedeker and Tom Lehman, the Open champion from 1996.

Closest to Johnson at the end of a day when 20 players out of the 156-strong field broke par, were 56-year-old Mark O’Meara, the Open champion from 1998, and rising Spanish player Rafael Cabrera-Bello, both of whom had 67s.

Tournament favourite Tiger Woods, playing competitively for the first time in a month after injuring his left elbow while hacking out of rough at the U.S. Open, stuck to the task and came away with a fine 69, which will do wonders for his confidence.

The opening day of the 142nd Open, however, will be remembered also for being a nightmare for two of the biggest names in the game ― former world number ones Rory McIlroy and Luke Donald.

Both failed abysmally to deal with the exceptional conditions at Muirfield, where two weeks of pure Scottish sunshine had left the famed links course running fast and furious.

More blue skies and temperatures passing 26 degrees Celsius on Thursday made the greens treacherous and at times Augusta National fast, especially around the pins, drawing criticism from several players.

World No. 2 McIlroy, desperately seeking the form that has eluded him since he changed clubs at the start of the year, had two double bogeys down the back nine en route to a demoralizing eight over 79.

The lowest point of his round came at the 15th where he shook his head in disbelief after watching his long putt speed over the rock-hard green and bury itself in a deep pot bunker.

A second double-bogey was the end result of that and he looked a disconsolate figure trudging off the 18th green with the question mark over his current form beginning to take on giant proportions.

“Sometimes I feel like I’m walking around out there and I’m unconscious. I just need to try to think more. I’m trying to focus and trying to concentrate,” he said.

“But I can’t really fathom it at the minute, and it’s hard to stand up here and tell you guys (press) what’s really wrong. It’s just so brain dead.”

Donald had a double bogey at 12 and a triple bogey two holes later and his score of 80 likely means that his hopes of finally winning a first major title are likely to once again be doomed.

Johnson, whose wedge play was key to his win in the 2007 Masters, this time looked to his putting to secure him the day’s best round of 66.

“It was a very solid day. I felt great,” said Johnson who lost out in a play-off won by 19-year-old American Jordan Spieth in the John Deere Classic on Sunday.

“Certainly coming into the week I felt great on the tee shots today. I felt pretty comfortable on my approach shots. I had some good numbers to hit some shots close, because that is part of it here, as firm as it is.

”Anytime you shoot under par in an Open or a major, for that matter, you have to be putting at least somewhat decent, and I putted great.“

Woods, who was matched on 69 by a group of players including old rival Phil Mickelson, said that any score at even par or better would have been acceptable to him.

“t was more of a grind than one of those Pro Am, happy-go-lucky, you know, talking to your playing partner all day. There wasn’t a lot of talking out there today because we’re trying to grind it out on that golf course, and it’s one of those courses where it just got so difficult,’he said

Defending champion Ernie Els had a 74 and U.S. Open champion Justin Rose a 75, while Australia’s Masters champion Adam Scott was happy to settle for a level par 71.

Nick Faldo’s return to Muirfield, where he won the Open twice, failed to find a spark as he struggled to a 78, while “golden oldie” playing partners, Tom Watson and Freddie Couples also found it tough going with a pair of 75s.

Three players withdrew with injuries ― 2010 Open champion Louis Oosthuizen of South Africa, and Swedish pair Peter Hanson and Alexander Noren.