National champion Stephen Mokoka set a personal best in the men's 10 000m final to steal the show on day one of the SA Student Athletics Championships in Stellenbosch on Friday.

Mokoka clocked 27:56.18 to better the World Championships B qualifying standard and elevate himself to fifth on the South African all-time list in the longest track event.

He was followed home by training partner Gladwin Mzazi who finished second in 28:09.33.

Apart from the domestic track season, Mokoka has had a busy start to the year, competing at the continental and global cross country championships in March.

He also finished second in a half-marathon in China on Saturday, clocking 61:42, and said he would revert back to pre-season strength and endurance training as he starts his build-up to the World Athletics Championships in Daegu, South Korea in August.

"It has been a long track season already; I have raced now solidly for four months," Mokoka said.

"It is time to put something back into the tank."

World 800m champion Caster Semenya, got her bid for four gold medals off to a solid start, securing the women's 1 500m title in 4:22.64 before dropping down in distance to win the 400m final in 53.18 seconds.

Triple South African 100m champion Simon Magakwe defended his men's short sprint title in 10.33.