Wayde van Niekerk continued his comeback from a serious knee injury by winning a 60m sprint event in Potchefstroom.
Since his return to the track, Van Niekerk has focussed mainly on 400m events but has said that he will also be running in shorter races.
And on Tuesday, he sprinted to victory in an unofficial time of 6.62 seconds.
Last week Van Niekerk won a 400m event in 45.89 seconds but took to Twitter after the race to say that he wasn't satisfied with his time.
In April this year, he told the Olympic Channel that he hoped to run below 43 seconds in the 400m.
"I am hungrier than before," he said.
"I still believe I can go sub-43. I can go way better than what I have in 100m and 200m, that’s where my mind was before the injury and that's where my mind is at for the future."