Danny Willett kept the pressure on Luke Donald at the top of the Nedbank Golf Challenge leaderboard heading into the final round at the Gary Player Country Club in Sun City.
Former World Number One Donald remains in pole position to win his first European Tour title since 2012 following a three under par 69 which left him one shot clear of Willett on 13 under.
Donald, who celebrates his 37th birthday on Sunday, said: “I'm pretty pleased with the score. I could have played a little bit more solid on the back nine, but to be honest, around this course, with a lead, shooting 69, that's kind of what the game plan was, to go out and shoot a low round and keep myself ahead and in position for tomorrow.
“I did that and felt pretty calm out there, and it was nice to finish with a three.”
His lead would have been even greater but he dropped shots on the 13th and 17th, his first since the sixth hole of his opening round, and fellow Englishman Willett surged into contention by carding a seven under par 65, the day’s best.
Like Donald, the 27 year old found trouble on the 444-yard par four 13th, his only blemish since Thursday.
Despite struggling to hit the heights of Friday, in which he recorded nine birdies, Donald managed gains on the fourth, seventh, ninth and tenth to sit four shots clear of the chasing pack.
However, that soon evaporated as Willett continued his charge on the back nine.
Willett gained a shot for the third consecutive hole on the 11th and, after both players found trouble on the 13th, he collected another birdie on the next.
Willett then completed the par three 16th in two shots to move within one of the lead.
Although he missed a putt to draw level on the penultimate hole, Willett was joined on 12 under when Donald failed to save par.
But the former Ryder Cup star showed his class on the last with a birdie that ensures he takes a slender lead into Sunday.
Donald added: “I'm excited to be in that position again. That's why we work hard and that's why we practise so much, and I'm excited for the challenge tomorrow.
"It will be nice playing with some of my compatriots, and we'll have some fun out there."
Willett said: "I was swinging nicely on the range, then made some really good moves on the first few holes which set up some relatively simple birdies, then I kept pressing. I didn't hold back and really pressed on and finished strongly."
Ross Fisher is still in contention, three shots off the pace following a second successive 70 which contained four birdies and two bogies.
The 34 year old said: “Tomorrow is going to be a big day. I just need to go out and play how I've been playing the first three days and how I putted on the first day.
“If I do that, I feel like I've got a really good chance of winning it.”
The next challenger to the three Englishmen at the top of the leaderboard is Marcel Siem, who is five under, while a shot further back are home favourite Louis Oosthuizen and Thailand’s Thongchai Jaidee.
The latter produced the shot of the day, holing a monster putt at the fourth for one of three gains en route to four under.
Spaniard Miguel Angel Jiménez, who got the 2015 season under way on Thursday, is one of three players on three under.
