The unusual sequence sparked thousands of comments on Twitter and Facebook, as many questioned if a scam occurred. The outcry prompted the country's lottery regulator to respond over the "public scrutiny" of the draw.
The South African Lottery Commission's internal investigation into Tuesday night’s lottery reportedly concluded the drawing wasn’t rigged.
"This occurrence, while uncommon, is not impossible," the National Lotteries Commission (NLC) said in a statement.
The odds of correctly guessing all five numbers and the PowerBall are one in 42 million, according to the operator, Ithuba Holdings.
In Tuesday's lottery, the draw's order was 8, 5, 9, 7, 6 and, for the PowerBall, 10.
"These numbers may be unexpected, but we see many players opt to play these sequences," the lottery said in a social media post following the live televised drawing.
The winners all split Tuesday's jackpot of 114 million South African rand, or nearly $7.5 million -- for about 5.7 million rand ($369,000) each.
Another 79 people correctly guessed the first five numbers, but not the PowerBall.
An Ithuba spokesperson denied accusations of fraud and urged winners to claim their prizes in a report by radio station Jacaranda FM.
The NLC issued a statement on Wednesday to "assure" South Africans about the lottery's integrity. The methods used to conduct the draws "undergo a rigorous process of review" to ensure that the lottery is "conducted with integrity and all players are afforded an equal chance of winning prizes," it said.
The operator's "random number generator" system also undergoes periodic testing to ensure integrity, and independent auditors and NLC officials observe the draws, it added.
The NLC said it received a report from Ithuba on Tuesday's drawing. Based on that, it only recommended that the operator educate the public on the odds of winning and how its random number generator system works.
In the national lottery, a player chooses five numbers between 1 and 50, and a single PowerBall number from 1 to 20. The five numbers do not have to be in order, while the PowerBall number has to match to win the jackpot.
Mathematician Grant Sanderson, who is behind the YouTube channel 3Blue1Brown, told ABC News that there's a one in 23,541 chance of a consecutive sequence like Tuesday's draw winning. Which, it turns out, isn't all that unusual.
"We should expect one-in-23,000-chance events to happen all the time," he said. "If every second there's a one-in-23,000 chance of something 'interesting' happening somewhere in the world, we'd expect there to be something 'interesting' about three to four times a day."
ABC News' Kirit Radia and Victor Ordonez contributed to this report.