South Africa’s Caster Semenya set a national record as she claimed victory in the women’s 1500m at the first Diamond League event of the season.
Semenya, who won gold in the discipline at April’s Commonwealth Games, posted three minutes 59.92 seconds in Doha.
The 27-year-old, who is a two-time Olympic 800m champion, could be impacted by new rules around testosterone levels in female runners.
When asked about the ruling, Semenya said: “I don’t talk about nonsense.”
Athletics South Africa said on Thursday it would challenge the International Association of Athletics Federations (IAAF) on the new rules.
IAAF chief Lord Coe has since said that the rules, which will affect track events from 400m up to the mile, are “appropriate for the sport”.
“I wanted to go faster, but had to slow down a little,” Semenya added.
“It’s always been a dream to set the national record and continue to push beyond my personal best. I think we definitely achieved what we came here for.”
Kenya’s Nelly Jepkosgei finished second in four minutes 0.99 seconds, with Ethiopian Habitam Alemu third.
Bradshaw stars in pole vault
Britain’s Holly Bradshaw placed second in the women’s pole vault after a first-time clearance at 4.64m.
America’s world indoor champion Sandi Morris cleared 4.84m to finish first, with Greek world champion Katerina Stefanidi finishing fourth with 4.64m.
Bradshaw’s compatriot Nethaneel Mitchell-Blake finished fifth in the men’s 200m, clocking 20.37 seconds.
Eilish McColgan, who represented Scotland at the Commonwealth Games, finished 12th in eight minutes 48.03 in the women’s 3,000m.
Elsewhere, Bostwana’s Isaac Makwala finished third in the men’s 400m.
Makwala, who won Commonwealth gold in the event, clocked 44.92 seconds, with Steven Gardiner of the Bahamas finishing first in 43.87 secs.
Jamaica’s Elaine Thompson, who claimed Olympic 100m gold in 2016, finished third in the discipline, in a season-best time of 10.93 seconds.
“I’m very happy to hit the podium – for me I’m looking ahead for the year and topping my personal best is one step on that journey,” Thompson, 25, said.
“I’m going to win another Diamond League, that is certainly in the future.”
There are 14 Diamond League meets in 2018, finishing in Brussels in August.
Semenya sets new national record in 1500m