Leendert Koekemoer Reaches World U20 400m Final

Leendert Koekemoer cruised to a heat-winning 45.18 in the semifinals of the men’s 400m at the World Athletics U20 Championships, booking his spot in Friday’s final and putting him one race away from a global age-group title.

The 19-year-old matched pace with Olympic 4x400m gold medallist Quincy Wilson, who won the other semifinal heat in 45.02. American Jayden Deleon, who beat Wilson at the US U20 Championships in June, took his heat in 45.49.

It capped a controlled couple of rounds for Koekemoer. He opened his campaign with a heat win in 45.75, doing just enough to advance without needing to find top gear early.

Leendert Koekemoer arrived in Oregon carrying the fastest South African U20 400m time in decades. He set the national U20 record at 44.94 seconds at the SuperSport Simbine Classic in Pretoria in April, becoming the first South African junior to break 45 seconds. That run erased his own previous best of 45.03, set the year before.

He trains at the University of Johannesburg under Lyle Wentzel, alongside reigning world U20 400m champion Udeme Okon. Leendert Koekemoer also isn’t new to finals under pressure — he was part of the South African 4x400m relay squad that won bronze at the 2025 World Championships in Tokyo, racing on the senior stage as a teenager.

Leendert Koekemoer, South African 400m sprinter:
“Being part of a senior team has helped me with my confidence.”

That composure showed in how he handled two rounds inside 24 hours at Hayward Field. The final goes off at 05:53 SAST on Saturday morning (8:53pm Friday in Eugene), with Koekemoer lining up against Wilson and Deleon in what shapes up as a rematch of their US U20 Championships showdown, where Deleon ran the second-fastest 400m in US high school history — 44.52 — to beat Wilson.

Start list, men’s 400m final: