Olympics and world 400-metre record-holder Wayde van Niekerk, who has been slowly recovering from a knee injury, won his first race this year in Bloemfontein Monday.
The 27-year-old South African finished first in a 100 meters race on grass in a hand-timed 10.20 seconds at an unofficial university meet.
Van Niekerk came though the race unscathed in the central city as he eyes the 2020 Tokyo Olympics and a chance to defend his 400meters title.
He smashed the Olympic and world 400 metres records of 43.18 set by American Michael Johnson in 1999 when he clocked 43.03 at the Rio Games four years ago.
His rehabilitation included medical treatment in the United States, Qatar and South Africa, where he is coached by a grandmother, Ans Botha.
The injury prevented him seeking a third consecutive world title in Doha last year after triumphs in Beijing in 2015 and in London two years later.