CAPE TOWN, South Africa -- Two 18-year-old female runners from Namibia won't be allowed to run in the 400 meters at the Tokyo Olympics after medical tests showed they have high natural testosterone levels.
That makes them ineligible under the same contentious rules that have sidelined South Africa's Caster Semenya.
The Namibian Olympic committee said Friday that the two runners, Christine Mboma and Beatrice Masilingi, had been withdrawn from the 400.
They will now "focus their full attention" on the 200 meters, Namibia's athletics federation said.
World Athletics' testosterone rules only apply to events between 400 meters and one mile.
Before this year, both teenagers were relative unknowns.
Mboma ran a blistering 48.54 seconds to win a 400 race in Poland on Wednesday, which was an under-20 world record and the seventh-fastest time ever recorded for a woman in the 400. It was also the fastest time in the world this year ahead of all the event's big names.
Masilingi's 49.53 seconds at a low-level meet in Zambia in April stands as the third fastest time of 2021.
The times spurred World Athletics to conduct "medical assessments" on the two at their current training camp in Italy, the Namibian Olympic committee said. The results indicated that both have high natural testosterone levels, the committee said.
"It is important to understand that both our athletes were not aware of this condition," it said.
The situation is reminiscent of the controversial sex verification tests conducted on a teenage Semenya at the 2009 world championships.
World Athletics' latest testosterone regulations have been fiercely debated since they were introduced in 2018.
They have resulted in Semenya, the two-time Olympic champion in the 800 meters, being unable to run in her favorite event and defend her title in Tokyo. She has launched legal appeals in various courts but has lost two appeals and is waiting for a third to be heard.
The rules have also affected two other high-profile African athletes, Francine Niyonsaba of Burundi and Margaret Wambui of Kenya, who won silver and bronze behind Semenya at the 2016 Olympics. They have both also been sidelined from the 800.