Overnight leader and reigning British Open champion Todd Hamilton shot a 3-under 69 and shares second place with Miguel Angel Jimenez, who carded a second-round 68. The duo is knotted at 9-under-par 135.
Heavy rain pelted the course for short intervals on Friday. Wind was up and play was contested under lift, clean and place for the second consecutive round.
Tiger Woods seemed to feel much better on Friday after back pain caused him to grimace and growl throughout his opening round on Thursday. In the second round, Woods did not show any outward signs of the injury he incurred while sleeping funny on a plane last week.
The two-time defending champion posted a 2-under 70 and is part of a group tied for ninth at minus-6.
'I feel much better today,' said Woods, who has three wins in four starts at this event. 'At least I could make somewhat of a turn and get the ball out there a little bit. Just still not quite right yet.'
Woods made two nice pars at the first two holes, then ran home a 15-footer for birdie at the fourth. He drained a 9-foot birdie putt at the seventh, and closed his front nine with a 32-foot birdie putt.
Woods three-putted the 12th green for his first bogey of the round. His second at the par-5 17th landed in a greenside bunker, but the No. 2 player in the world blasted out to 3 feet to set up birdie. Woods came up short with his approach at the closing hole and left with bogey to fall five behind Els.
'I had two three-putts and left two short ones there, so four putts right there, four shots. I could have been at 10 under par easily,' admitted Woods. 'If I would have putted better, I could have shot 66 no problem today. I just had four holes where I just spent a little more time on the greens than I should have.'
But Els' play was a bigger story than Woods' back on Friday.
The South African flew out of the gate in the second round. He rolled in a 4-footer for birdie at the first and made it back-to-back birdies with a 12-footer at the second. Els hit his tee ball to a foot to set up his third consecutive birdie at the par-3 third and made it four in a row with a 20-foot birdie putt at No. 4.
'I got off to a perfect start,' said Els. 'I knew it was going to be rough today. I actually took my time getting out to the range this morning. I normally take an hour to get out there, but today I waited and waited.'
The wait was worth it for Els.
He sank an 18-foot birdie putt at the ninth to go to minus-8 and take a two-shot lead. Els could not reach the green in two at the 10th because the rain was coming down hard. His second landed in a greenside bunker, where he blasted out to 7 feet and converted the birdie putt.
Els dropped his first shot of the round at 11. His 7-iron tee shot at the par-3 hole went through the green, but he chipped to 4 feet. Els missed the putt, but would atone for the mistake later in his round.
At the 14th, Els hit a 5-iron 10 feet behind the hole and made the putt. He added another birdie at 15 when his pitching-wedge second shot stopped 4 feet from the hole. Els failed to land on the green with a 3-wood at the par-5 17th, but he chipped to inches and tapped in the birdie try.
Els holed a clutch 10-footer for par at 18 to preserve his two-shot advantage.
'I'm leading at the moment, but leading right now doesn't mean much,' said Els, who has not won since the Memorial at the end of May. 'We've got a lot of golf to be played and I've got a lot of birdies to be made.'
Hamilton, who defeated Els in a playoff at Royal Troon to win the claret jug, hung with Els when the South African took the lead. Hamilton birdied the second and the par-5 eighth to make the turn at 2-under 34.
Hamilton never got anything going on the back nine after a 5-foot birdie putt at the 10th. He parred his final eight holes, including a tough 5-footer at the 15th, to stay within two of Els' lead.
'I've played well the last couple of days,' said Hamilton. 'It's easy to enjoy your golf when you're not making bogeys. I kept the round going. I had some good chips and made some good putts.'
Jimenez was even through 10 holes, but got going on the back nine. He birdied the par-3 11th and added another at 16. The Spaniard drained a 50-foot eagle putt at the 17th and hit a spectacular third shot to save par at the 18th.
Justin Leonard, the 1997 British Open champion, who lost in a playoff at the PGA Championship, carded his second 4-under 68 in as many days to take fourth at 8-under-par 136.
Lee Westwood, Thomas Bjorn, and current reigning U.S. Open champion Retief Goosen all posted rounds of 3-under 69 and are tied for fifth place with Steve Flesch, who shot a 70 on Friday. The group is knotted at 7-under-par 137.
Woods was joined in ninth by local favorite Padraig Harrington (69), his Ryder Cup teammates David Howell (69) and Luke Donald (71), Brad Faxon (68) and Angel Cabrera (69).
Sergio Garcia, who held the lead throughout much of Thursday's opening round until Hamilton went by him, only managed an even-par 72 on Friday and is part of a group tied for 15th at minus-5.