Fichardt's round gave him a 54-hole total of 11-under-par 202, a shot clear of first round leader Grant Mulle. Muller matched his 67 and finished one ahead of the winner of the Vodacom Players Championship, Trevor Immelman, who made three birdies in his last six holes en route to a 69.
On a widely spread leader board, Englishman Mark Hilton was three off the pace after a 68 and Steve van Vuuren, who hails from nearby Nelspruit, was four behind Fichardt after his third straight round under 70, a 69.
Fichardt, who said he had been making some swing changes with a coach in Spain, got off to a slow start, his putter coming to his rescue on three of the first four holes after he'd missed the green. 'My putter got me through the first few holes,' he said.
On the fifth and sixth, he added to his birdie four at the second, jumping out to 10-under-par and a three-shot lead. Overnight leader Keith Horne faded on Saturday with a 76, and Richard Kaplan, one off the halfway pace, both started with bogeys, Horne adding a second at the par-4 3rd.
Muller had picked up a shot at the third and another birdie at the ninth, where he overcame one of a number of tricky pin positions, got him to within two shots, but Fichardt immediately extended his advantage to three again at the 10th, despite his drive finishing in a fairway bunker.
The 25-year-old from Pretoria unlike many of his fellow pros, drained a birdie from 5m after going in with a 7-iron.
His first major problem of the round came shortly afterwards, when his tee shot on the par-5 13th 'caught a rock or something and went straight left into the long grass'. Forced to declare it unplayable and take a penalty drop, Fichardt hit a 5-wood just short of the green, but for once couldn't get up and down for par.
Typically of his fighting round, though, the man who topped last year's order of merit after finishing second in the SA Open, struck back with a birdie, hitting a wedge close at the 14th.
The course bit back at the long par-4 15th. His drive finished in a bunker running alongside a lake which guards the green. 'I had 200m to the flag, but the pin was 20m on, so it was 180m to the front. I took a 3-iron, but I hit it a little fat and it went in the water.'
That resulted in a double-bogey six, but Fichardt, who lost his sister in a tragic accident just over a month ago, showed incredible character to bounce back again at the 16th, holing a putt of some 50 feet for birdie. 'That was huge,' was all he could say about the viciously swinging putt.
At the par-5 18th, a 6-iron approach gave him a putt for eagle, but he 'left it in the mouth' and settled for a birdie to lead on his own.
Muller should have been alongside on Fichardt on 202, but for his mistake in giving himself a four on the sixth hole, when he had taken a three, in Friday's second round. Muller, who said he had gone through his card three times without picking up the error, was asked how important that shot might be. 'I'll tell you after tomorrow's round. Please God, it doesn't cost me,' he replied, adding: 'The only way I can ify that shot is to win the tournament. If I finish second or third by a shot, I'll know how much it cost me.'