Bjorn carded a 6-under 66 to come in at 13-under-par 203. European Ryder Cup teammates David Howell and local favorite Padraig Harrington posted matching rounds of 66 on Saturday and are tied for third with reigning British Open champion Todd Hamilton, who shot a third-round 69. The trio is knotted at minus-12.
The wind was heavy at times on Saturday and weather is expected to be a problem on Sunday. The forecast calls for rain and significant wind gusts in the morning.
Tiger Woods, who battled back problems in the first round, continued to improve physically and fashioned his second consecutive round of 2-under 70 on Saturday. He is part of a group tied for eighth place at 8-under-par 208.
'Certainly it's still sore, but at least I can now move and make a golf swing at it,' said Woods, the two-time defending champion. 'I'm still six shots back, which is a long way back, especially when Ernie is playing the way he is.'
By the time Els teed off on Saturday, several players were in the midst of low rounds. Els did not get off to a great start with four pars to open his round, but broke into red figures with a birdie at the fifth.
Els ran home an 18-foot birdie putt at the eighth to reach 13 under par and go ahead by one. He missed the green with his second at the ninth, and his pitch came up nine feet short. Els' par putt came up short, so the South African fell into a tie for the lead with Bjorn and Harrington.
But Els rebounded. His second at the par-5 10th hit the green, but bounced into the back bunker. Els blasted out to four feet and converted the birdie putt. He got to 14 under for the tournament with a birdie at No. 11.
None of his closest pursuers could wrestle the lead from Els late on the back nine. Els extended his margin at the par-5 17th with a birdie and had a decent look at birdie at Mount Juliet's demanding closing hole. His approach landed 20 feet from the pin on the fringe, but his birdie putt caught a piece of the hole, but never fell.
Still Els has the 54-hole lead in a WGC event and can lock up his first individual victory in this series. Also, if Els can make his way to the winner's circle on Sunday, he will go past Woods into second in the Official World Golf Ranking.
'I worked hard to get to where I am, so I've got a two-shot lead and it's good to be in that position again,' said Els. 'I've got good goals that I still want to achieve in my career and I want to just start working hard again.'
This was a most-unexpected round for Bjorn, who walked off the course the last time he played in Ireland at the European Open. He was frustrated with his game, but is now in position to win.
'I'm very well aware that tomorrow is a big day for me, but nobody can take away the first three days from me, and my golf is certainly going in my direction at the moment,' said Bjorn, who served as one European Ryder Cup captain Bernhard Langer's vice-captains. 'I'm going to go out and try and enjoy this tomorrow, because when you go through a hard time, this is where you want to be.'
Bjorn came out strong on Saturday with birdies at one and two. He eagled the par-5 fifth, but did not card his next birdie until the 10th, when he sank a 10-footer.
Bjorn added a 12-foot birdie putt at the 13th that briefly tied him for the lead. He failed to add any more birdies on the way in, but will play with Els and Howell in Sunday's final threesome.
'I played some good golf,' said Bjorn. 'There was a couple of iffy shots in there, but I guess that's to be expected when the weather is like this. I'm very happy with what I did today.'
Howell mixed three birdies and a bogey on his front side, but it was his play at the beginning of the second nine that vaulted him up the leaderboard. He two-putted from 20 feet for birdie at 10, sank a 22-foot birdie putt at the 11th and knocked a 6-iron to 3 feet to set up birdie at 12. Howell, who went 1-1 in the Ryder Cup, tapped in a 3-footer for birdie at 17 to get within three.
Harrington was flawless in his 66 on Saturday, but did most of his damage on the front side. He made a 15-footer for birdie at one, then drained a 25-foot par save at the second. The Irishman made a 15-footer for birdie at three and made it two in a row at four with a short putt.
The Irishman holed a pair of 15-foot birdie putts at eight and nine, then collected his third straight birdie with a 3-footer at No. 10. Harrington will be in search of his first win on home soil, and the crowd is definitely pulling for him.
'I've gotten some great support,' said Harrington. 'Thankfully I started the right way and it gave some momentum to that crowd. There were some really, really good moments out there.'
Reigning U.S. Open champion Retief Goosen carded a 4-under 68 and is alone in sixth place at 11-under-par 205. Sergio Garcia fired a 5-under 67 and has seventh by himself at minus-10.
Woods was joined in eighth by Darren Clarke (65), the only other player beside Woods to win multiple WGC crowns, Zach Johnson (69) and Lee Westwood (71).