Ockie Strydom matched Scott Jamieson's course-record 63 to join the Scot at the top of the leaderboard heading into the final round of the Alfred Dunhill Championship.
Jamieson followed Friday's record-breaking effort at Leopard Creek with a two-under 70 to sit on 15 under alongside Strydom, who raised South African supporters' hopes of another home champion with a surge up the standings.
The 37-year-old is yet to win on the DP World Tour but gave himself every chance as he eagled the second to set the tone for a third round featuring eight birdies between the fourth and 15th.
He said: "I'm just doing the same as what I've been doing every day. I'll play golf - if it comes out, it comes out. If it doesn't, you've still got next week to go."
But for a bogey at the short 16th, Jamieson's record would have stood for just 24 hours but as it was, Strydom had to settle for equalling it as he finished with two pars.
Jamieson, the overnight leader, steadied himself after an up-and-down front nine featuring three bogeys and two birdies, coming home in 34 for a share of the lead, with the pair's nearest challengers two shots back on 13 under.
That three-strong group is made up of South African pair Oliver Bekker and Dean Burmester, both of whom carded four-under 68s, and England's Dale Whitnell, whose 66 featured two eagles - one of them holed from a greenside bunker at the driveable par-four eighth.
The tournament has had a home winner in seven of the past nine editions, and the list of candidates to make it eight in 10 also includes Branden Grace and Dylan Frittelli, who are three back on 12 under along with Adrian Otaegui of Spain, whose round of 65 was bettered only by Strydom on the day.
English pair Nathan Kimsey and Eddie Pepperell began the day tied for second on 10 under but shot 74 and 73 respectively to drop off the pace.
Watch the final round of the Alfred Dunhill Championship live on Sky Sports Golf from 8.30am on Sunday.