Defending champion Branden Grace set the clubhouse target on day three of the Alfred Dunhill Championship, but he was in danger of being overshadowed by European Tour rookie Sébastien Gros.
Grace scraped into the weekend at Leopard Creek Country Club on level par and took advantage by firing a third-round 66 to get to six under and into a share of third place.
But Frenchman Gros, who is playing just his second European Tour event after finishing second on The Challenge Tour last season, made nine birdies in his first 16 holes to move to ten under and one shot back of overnight leader Charl Schwartzel.
Three-time winner Schwartzel came into the weekend with a five-shot lead and looked like he could run away with a tournament which he admits is his favourite on The European Tour International Schedule.
Grace and Gros have shown that there are low scores to be made on Saturday, though, when the leading groups get under way in the afternoon.
Six-time European Tour winner Grace came into the week in good form after a third-place finish at the DP World Tour Championship, Dubai and The Race to Dubai but struggled to find his best form over the first two days as he went 71-73.
He was in the second group out on Saturday and birdied the second but gave the shot straight back before gains on the sixth and eighth saw him turn in 33. A hat-trick of birdies from the 13th then catapulted him up the leaderboard and a closing birdie got him to six under.
"I didn't really miss any shots," he said. "The putter wasn't warm at all. I probably left another four out there so it could have been a lot better but it's still good.
"It was a good moving day for me but there is still tomorrow, I need a real low one tomorrow.
"If I can get into the top five, top ten then it would be a good defence."
Gros was a two-time winner on The Challenge Tour last season and looked on course to go out in the late groups on Saturday before three dropped shots in the last three holes of his second round derailed his progress.
But birdies on the third, fifth, sixth, seventh, tenth, 11th, 13th, 15th and 16th moved him right into contention on day three.
South Africans Dylan Frittelli and Jbe Kruger were in the group at six under on the back nine of their third rounds.
