Kevin Phelan, who shared the overnight lead at the Africa Openwith England's Matt Ford, could only add a 72 to his opening 67 to remain five under at East London Golf Club, one ahead of newly appointed Ryder Cup captain Darren Clarke, who carded six birdies and two bogeys in a 68.
Ford will take a narrow lead into the third day after carding a second-round 66.
Ford took advantage of calmer conditions for the morning starters to card six birdies and an eagle, with his only blemishes coming on the ninth and 17th.
That left the 36-year-old 11 under par and one ahead of Spain’s Eduardo de la Riva, who also returned a 66 containing eight birdies and two bogeys.
Ford, who was about to spend a winter working for Royal Mail before coming through November’s European Tour qualifying school at the 10th attempt, said: “I don’t think you can ever get all of it out of the round.
“I missed a short one on 17 and hit a poor tee shot off nine, so those were a couple of mistakes, but you’re always going to make a few of those. I would have taken 11 under at the beginning of the day.
“I missed a couple of putts but I holed a couple and I holed a wedge (from 119 yards for his eagle on the par-four 12th) so I played some good stuff. I’ve been hitting it pettty steady all year and the way the golf course is suits me; you are not hitting full out shots, you are hitting quite a lot of half shots. I’ve had good control of the ball so far this week.”
Both of De la Riva’s bogeys came in his first three holes, but the world number 369 responded with a flurry of birdies to keep Ford well within in his sights.
“I played a very good round today with good golf and good putts. I am very happy with the first two rounds,” he said.
South Africa have provided all five previous winners of this event and four home players were inside the top seven on the leaderboard, with Jaco van Zyl and Erik Van Rooyen three off the lead on eight under alongside France's Gregory Havret.
Van Zyl, who finished joint second the Joburg Open on Sunday, also shot 66 and said: “Yesterday was really tough out there and I was very chuffed to pull two under out of it. I got it a lot easier this morning and when that happens you try to capitalise.”
Van Zyl's compatriots Neil Schietekat and Trevor Fisher were one shot further back along with English pair David Howell and John Parry, Chile's Mark Tullo and Germany's Max Kieffer, whose 63 was the lowest score of the day.
England's Andy Sullivan, who was seeking a third win in South Africa in nine weeks, missed the cut after a disappointing 77 left him five over par.
