Pappas, the third of the four golfing brothers from Phalaborwa, fired a five-under-par 67, the same as runner-up Don Gammon, who had started the final day three shots adrift, to record a 19-under-par total of 269.
It was a day of high drama which came close to descending into farce when one of his third round co-leaders, Sammy Daniels, did his Jean van de Velde impression, shedding his footwear at the par-four 15th to hit his second out of a water hazard en route to a bogey five.
That brought to nine the number of strokes Daniels had shed in a rollercoaster round of 75 that also included six birdies. His unscheduled paddling session had been preceded by a triple-bogey six at the 12th and another six, this time a double, at the next.
Pappas, who lives in Orlando, Florida, said his concentration hadn't been affected by Daniels' tribulations. (My caddie) Mark (McCann) and I just stood there and talked about whatever came to mind. That's the way it goes. Sometimes you've just got to wait and get back into your routine when it's your turn,' he said.
His other playing partner, Pretoria rookie Martin Maritz, was also struggling.
He started the day bogey, double-bogey, a shot worse than Daniels' bogey-bogey at the first two holes, all of which allowed Pappas to jump into a three-shot lead after a birdie at the first hole, which proved one of the toughest on the new lay-out all week.
Daniels did get back to within a shot at one stage, after a birdie two at the seventh, before his round imploded, but the real challenges to Pappas' leadership came from further down the field, particularly from Gammon, who had held a share of the halfway lead after Friday's second round. Out in four-under-par 32 to Pappas' 34 - the eventual winner made his only major mistake with a three-putt at the ninth for his sole bogey - Gammon birdied the par-five 11th hole to draw level with Pappas, who was playing the 10th, at 16 under.
Gammon's share of top spot was a shortlived one, however. When his turn came at 11, which he said was 'playing the longest it had all week' because the wind had shifted and was blowing into the players, Pappas rammed in a 35-footer for eagle to jump out to a two-shot advantage which was never cut. A birdie three at the 16th, which he described as 'probably the toughest hole out there today, with the pin in the back corner', finally assured him of what he described as 'definitely' his biggest win. His previous professional victories had consisted of 'a couple of mini-tour wins' in the United States and the Cleveland Open on last year's BUY.COM tour.
'The key today was to make no mistakes, no mental errors. We kept it in play all day,' he said, using the collective term to include his trusty caddie, who started out teaching him and has been on the bag for a couple of years now.
Clearly not a man given to great displays of emotion, the 33-year-old was nevertheless delighted to have broken his duck on home soil with such a prestigious title. 'I had a look at the trophy there and it's got all the great names,' he said.
With Daniels and Maritz, who made a 71 for a share of third place, falling off the pace, Sunday was an opportunity for players further back to come through the field and several took advantage, none more so than Roodepoort's Hendrik Buhrmann, who equalled the course record with a seven-under-par 65 and saw a 25-foot birdie putt lip out on the 18th to rob him of a 64. He finished four back, level with Maritz, Alan McLean and Nic Henning.
Ireland's Peter Lawrie matched Buhrmann's round, moving from one under par to a share of 20th spot on a 72-hole total of 280.