France's Sasha Zhoya broke the men's under-20s 110m hurdles world record for a second time in 24 hours on Saturday to claim the title at the age group World Athletics Championships in Kenya.
Zhoya, 19, who was born in Australia to a Zimbabwean father and French mother, ran 12.72 seconds to claim gold which improved his semi-final time on Friday by 0.21sec.
"I'm very happy, the job is done, since last year it was the objective I gave myself," Zhoya told World Athletics.
"Today in the warm-up I had some pain in the hips. It's difficult but the life of an athlete is to manage that," he added.
Jamaica's Vashaun Vascianna finished in second place with a time of 13.2sec with Poland's Jakub Szymanski third on 13.43sec, with the pair running personal bests.
Later in Nairobi, Olympic silver medallist Christine Mboma and her Namibian teammate Beatrice Masilingi race in the women's 200m final at 1500GMT.
Masilingi, who took silver in Thursday's 100m final behind Jamaica's Tina Clayton, was the fastest of the finalists as she won her semi-final in a championship record time of 22.19sec.
Both Mboma and Masilingi are unable to compete at certain events due to differences in sexual development (DSD) and classified as "intersex" athletes with naturally high testosterone levels.
Under World Athletics rules, the two sprinters' rare physiology is deemed to give them an unfair competitive advantage in track events ranging between 400m and one mile.