Louis Oosthuizen came home in 30 to set the clubhouse target as he looks for his first win at the South African Open hosted by the City of Johannesburg.
The home favourite has been one of golf's biggest stars for a decade, winning The Open Championship and multiple titles on the European Tour but he has never before won his national Open.
He is the highest-ranked player in the field this week and lived up to that billing on day one, signing for a 62 and a nine under total to sit three shots ahead of English playing partner Matt Wallace.
The duo were playing the Bushwillow Course at Randpark Golf Club, with that layout producing much lower scores than the longer Firethorn on Thursday.
Home favourites Ernie Els, Branden Grace and David McIntyre were also playing the Bushwillow and they were four shots off the lead alongside German Max Schmitt - who had played Firethorn.
Wallace shared the early lead at four under with gains on the first, second, third and fifth, and Els joined him with a hat-trick from the seventh after birdieing the first.
A fourth birdie in a row had Els in the solo lead and he made another on the 12th before dropping his first shot of the day on the next.
Wallace had dropped a shot on the eighth but he birdied the tenth from six feet and 11th from ten to get into the lead alongside home favourite Oosthuizen.
The 2010 Claret Jug winner also birdied the tenth from six feet and 11th after a stunning approach to go with gains on the first, fifth and seventh.
The playing partners each made it a hat-trick of gains on the par-five 12th but it was all change on the 14th as Oosthuizen holed an eight-footer and Wallace dropped a shot to put the 36 year old ahead.
An 18-foot right-to-lefter on the 16th then put Oosthuizen three ahead as Els parred his way home to join the clubhouse lead at five under.
Oosthuizen went over the back of the green at the par-five 17th but got up and down to briefly lead by four before Wallace followed him in.
Grace made three birdies in a row from the third and after a dropped shot on the ninth added gains on the 11th and 12th before holing a 15-foot left-to-righter on the 15th.
McIntyre had birdied the first and fifth and while he dropped a shot on the eighth, he came home in 32 with gains on the 11th, 12th, 16th and 17th.
Qualifying School graduate Schmitt made birdies on the second, seventh, ninth, 11th, 12th and 16th to go with a bogey on the third.
South African Jake Roos, Zambian Madalitso Muthiya and Frenchman Matthieu Pavon were out on the course at five under.
