England's Lee Slattery stormed into the lead at the Alfred Dunhill Championship, shooting a bogey free round of 65 at Leopard Creek to move to six under par for the tournament.
Playing the back nine first, the 29-year-old started slowly with two birdies, before adding five more in the second nine to move one stroke clear of the field.
The other big mover in near perfect conditions was home favourite Ernie Els with a three-under-par 69 adding to his 70 on day one.
But things could have been much better for the big South African, who also dropped several shots along the way with four bogeys.
England's Richard Bland shot a two-under 70 to move to five under par and stay second alongside Els and overnight leader Sion Bebb.
The Welshman upstaged most of the big names yesterday with a round that included six birdies and a bogey, while Craig Lee - second overnight - slipped back to level par.
Darren Clarke leads the Irish challenge on two-under par, six off the leader. The Tyrone man carded a second round 69 that included five birdies and two bogeys.
Dubliner Stephen Browne is also on two-under par and is level for his second round through seven holes.
But it was Slattery who made the biggest impact, admitting his lead could have been even bigger than just the one stroke.
He said: "I'll be honest with you, I even left a few chances out there today. It's probably the best I've hit the ball tee to green for a long time. It was great.
"I just holed a few putts early on. That was the key. Holed one off the green and that obviously helps. I just think in general I was just swinging the club nicely and just hitting a lot of good shots.
"I would love if the conditions stay like this. With this sort of cooler climate and a slight wind only, it does help me."
:quality(70)/cloudfront-eu-central-1.images.arcpublishing.com/irishtimes/YVIRIOZQ35EWRPZXR27KGMO6YU.png)