Ockie Strydom equalled the course record set by Scott Jamieson a day earlier to join the Scot at the top of the leaderboard on day three of the Alfred Dunhill Championship.
South African Strydom stormed into contention on Moving Day, carding an eagle and eight birdies in his first 15 holes before a late bogey prevented him from setting a new course record at Leopard Creek Country Club.
He instead had to settle for a third-round 63 and a share of the lead alongside Jamieson heading into Sunday's fourth round.
Halfway leader Jamieson struggled on the front nine on Saturday, carding three bogeys and two birdies to turn in 36.
But he bounced back with three straight birdies at the 11th, 12th and 13th to join Strydom on 15 under par.
The leading duo sit two shots clear of South Africans Dean Burmester and Oliver Bekker and Englishman Dale Whitnell in a three-way tie for third.
Strydom began the day seven shots off the lead but soon set about closing the gap, firing a stunning eagle at the second before making a hat-trick of birdies at the fourth, fifth and sixth.
Further gains followed at the ninth and 11th before he rolled in from around 25 feet for another on the 13th.
The home favourite opened up a three-shot lead after sending his approach at the 14th to four feet and sinking the putt.
And he made it three birdies in a row on the 15th, having narrowly cleared the water with his second shot and two-putted for birdie.
That took him to ten under for the day, and with three holes remaining, the possibility of a 59 was not out of the question.
But he was unable to save par at the short 16th, and had to settle for pars at the 17th and 18th to head into the final round on 15 under.
Strydom was pleased with his eagle at the second. He said: "I left it in an impossible spot on the second hole, short of the bunker right.
"And I had a steep bank, probably a foot or two to work with, and pitched it exactly where I wanted to and it just went in."
He vowed not to change anything as he aims to win his maiden DP World Tour title on Sunday.
Strydom added: "I'm just doing the same as what I've been doing every day.
"Play golf - if it comes out, it comes out. If it doesn't, you've still got next week to go."
Scotland's Jamieson went into day three with a three-stroke lead and birdied the long second to move to 14 under.
But back-to-back dropped shots at the fourth and fifth stalled his progress before he recovered with a birdie at the sixth.
He gave the shot straight back at the par-three seventh, though, and turned in 36 after parring the eighth and ninth.
Jamieson's fightback began at the 11th, where he holed from more than 20 feet for a birdie, before further gains at the 12th and 13th earned him a share of the lead on 15 under.
He continued to give himself chances on the way in but parred his final five holes to sit alongside Strydom with 18 holes remaining.
Jamieson is looking to make it a South African double, having won his only DP World Tour title so far there at the Nelson Mandela Championship presented by ISPS HANDA ten years ago.
Jamieson said: "It was a solid day. As expected, the course was a little tougher today, the green speeds were up a little bit on yesterday.
"I didn't get off to the best of starts on the front nine, I hit poor shots on the fourth and fifth which kind of killed the momentum.
"Then you get seven and eight - two really tough holes.
"One over at the turn wasn't a disaster, I knew there was going to be chances on the back nine - and I hit three in a row on the back nine.
"So yeah, two under was a good day."
Looking ahead to the final round, Jamieson said: "It's why we play golf. There's some good names up there so it's going to be an exciting day."
