Sergio Garcia was pegged back on the second day of the Nedbank Golf Challenge in South Africa.
The Spaniard, looking for back-to-back victories after triumphing at Valderrama, shot an eight-under-par first round to lead by four but goes into the weekend just one ahead of home favourite Louis Oosthuizen.
Garcia extended his lead to five shots with birdies at the first two holes but had to sign for a one-under-par 71 after three bogeys in the last six holes at Sun City.
Garcia, who is nine under par, said on europeantour.com: "The course is tough. It's not every day you're going to go out there and shoot 64, it doesn't work like that. I feel like I played quite well.
"I stayed positive, I stayed calm. I wanted to shoot something below 70 and I felt like I had a chance of doing it, unfortunately it didn't work out but we're still in the lead. It's good."
A double-bogey at the eighth was the only blemish on Oosthuizen's card of 67, with his round also including three birdies in the first four holes, an eagle at the 10th and further birdies at 14 and 15.
Finn Mikko Korhonen sits third, three shots off Garcia, with English pair Lee Westwood and Aaron Rai, South Africa's Dylan Frittelli and Ireland's Shane Lowry a further two shots back on four under after a 3 under par 69.
Rory McIlroy, who needs a top-two finish to keep his Race to Dubai hopes alive, is one under par after a second-round 71.
A second consecutive 73 from Padraig Harrington leaves the three-time major winner on two over, while Paul Dunne is five over at adding a 71 to yesterday's 78.