Tiger Woods did not capitalise on a strong start, three under through six holes, closing with a pedestrian two-under 70, while Phil Mickelson withdrew after 11 holes due to a left-wrist injury.

Els, putting cross-handed for the first time over an entire round, stormed home with five back nine birdies.

“I’ve had a pretty tough time for most part of this year,” said the South African, who is coming off a tie for 24th at the European Tour’s BMW PGA Championship last Sunday.

“My game hasn’t been really good, especially the last three weeks, especially on the greens. I’ve been very uncomfortable, very frustrated.”

Els, who has not won on the PGA Tour since 2004, was so frustrated last Sunday that he experimented putting cross-handed the final nine holes, and the initial results were positive.

“It was a tough decision to make, when you’ve putted the conventional way all your life and been a pretty good putter, to go the other way,” said the three-time major winner. “But the path of the stroke is pretty good, and that’s all that counts, I guess.”

Els was far from flawless, but he used a sharp short game to extricate himself on the few occasions he was in trouble.

“It wasn’t a perfect round, but I had a bunker shot that went in on 13 for birdie, and I chipped in for par on 17. So I made a couple of mistakes here and there, but I felt comfortable.”

He joined Aaron Baddeley, Bubba Watson, Tim Herron and Ryan Moore in a tie for third, while O’Hair, Pampling and O’Hern led with seven-under 65s.

O’Hair is making his first appearance since the Players Championship, where three weeks ago he challenged Mickelson for victory until a quadruple bogey at the penultimate hole.

But O’Hair seems to have put that disappointment behind him, and his swing is certainly still in the groove.

“I started hitting the ball well from the beginning,” said O’Hair, who had eight birdies in the first 13 holes before cooling off slightly, dropping a shot at the 17th.

“I was picking good targets and hitting the shots the way I wanted, most of them anyway. I rolled the ball great (on the greens) too. My speed control was really good.”

Pampling’s card was identical to O’Hair’s on the front nine, both players making birdies at the same five holes.

Pampling has been playing well lately without much to show for it, due, he says, to an uncooperative putter, but he had no trouble finding the hole on Thursday, draining nine birdies, including a 20-footer at the last.

“I was thankful I had a few good reads off my playing partners, which certainly helped make some putts, and I finished off the last with a nice birdie,” said the two-time PGA Tour winner.

Fellow Australian O’Hern made his move late, picking up five birdies in a scorching six-hole stretch starting at the 11th.

“A round like this has been in the makings,” said O’Hern. “It’s been a long time coming, but I’ve put in a lot of hard work and it’s starting to pay off.”

Woods, meanwhile, lamented what might have been: “I had it going through six (holes) and made just a terrible bogey at seven and a few more mistakes after that.

“It’s a little frustrating in the sense I had an opportunity to shoot four, five, six under today. Today was just a great day to score. The course was playing pretty benign.”