Double Olympic champion Caster Semenya will run her last 800-metres on Friday before the International Association of Athletics Federations imposes hugely controversial new rules limiting testosterone in female athletes.
Semenya, who has spent years trying to get the new IAAF regulations thrown out, will compete at the Diamond League meeting in Doha against 2016 Olympic silver medallist Francine Niyonsaba - who recently revealed she had similar difference in sexual development (DSD) characteristics to the South African.
Both must then begin taking medication to lower their testosterone levels if they wish to compete over that distance based on the new rules, which the Court of Arbitration for Sport (CAS) said on Wednesday were necessary to ensure fair competition.
IAAF president Sebastian Coe, speaking in Doha on Thursday, said he was grateful to CAS for the verdict.
"It is very straightforward for any association in sport," Coe told a media briefing.
"Athletics has two classifications - it has age and it has gender. We are fiercely protective of both. We are really grateful that CAS has upheld that principle."
Coe refused to take more questions, but the case is likely to have far-reaching consequences for women's sport, and has split opinion around the globe.
Athletics South Africa likened the new IAAF regulations to apartheid, and both it and Semenya's lawyers have said they could contest the CAS ruling dismissing her appeal against their introduction.
Under the rules to take effect on May 8, female athletes with high natural levels of testosterone wishing to compete in events from 400-metres to a mile must medically limit that level to under 5 nmol/L, which is double the normal female range of below 2 nmol/L.
Testosterone increases muscle mass, strength and haemoglobin, which affects endurance. Some competitors have said women with higher levels of the hormone have an unfair advantage.
Barring further legal action, Semenya finds herself at a crossroads: Either she submits to the regulations or looks to compete in longer distances.
She claimed the 5,000-metres title at the South African Athletics Championships last week, an event not covered by the IAAF regulations, but in a modest time of 16:05.97, well below the qualifying standard for the world championships of 15:22.00.
This potential lifeline means Semenya may not abandon the 800-metres yet, though any advance to the Swiss Federal Tribunal could take months to reach a verdict and leave her career in limbo.
Former sprinter Michael Johnson, who won four Olympic gold medals between 1992 and 2000, believes the regulations are right for women's athletics.
"It was always going to be a difficult situation because through no fault of her own she just happens to have this condition," Johnson told Reuters.
"The IAAF has to make a decision on the line that's drawn between the female races and the men's races. I think the decision was based on the fairness of sports, so that there is a level playing field for all of the athletes in any given race."
Semenya, 28, has vowed to fight on, whichever distance she races in.
"I know that the IAAF's regulations have always targeted me specifically," she said in a statement released via her lawyers on Wednesday.
"For a decade the IAAF has tried to slow me down, but this has actually made me stronger. The decision of the CAS will not hold me back. I will once again rise above and continue to inspire young women and athletes in South Africa and around the world."
Her personal best of 1:54.25 in the 800-metres will make her the quickest in the field in Doha’s Diamond League meet, the first time she will compete over the distance in 2019.
Tongan Taufatofua looks to be dual threat in Tokyo
Tongan Pita Taufatofua, who set social media ablaze when he went shirtless during the opening and closing ceremonies in the past two Olympics, on Wednesday said he is aiming to qualify for the 2020 Summer Games in Tokyo in two sports.
The Australia-born 35-year-old hopes to make a second appearance in taekwondo while also hunting for gold in sprint kayak, which he said he only took up recently.
"Taekwondo is my first love. You never forget your first love," he told Reuters at a training session in New York.
"We're trying to do two sports in one Olympics."
If successful he will be the first person in the modern era to compete in three completely different Olympic sports following his unlikely foray into cross-country skiing in Pyeongchang last year.
Taufatofua says his interest in kayaking comes from the canoeing and paddling traditions of his Tongan ancestors.
"Kayaking is a sport that is part of being a Polynesian. They traveled all throughout Polynesia hundreds of years ago and that's more of a natural sport to me than, say, the skiing, and I just love being out on the ocean."
The image of Taufatofua -- oiled up, shirtless and wearing a traditional Tongan ta'ovala (mat) at the head of the country's tiny delegation at Rio's Maracana stadium in 2016 -- went viral online.
Taufatofua became the first UNICEF Pacific ambassador and made an appearance at UNICEF headquarters in New York in that capacity.
In addition to his passion for the Olympics he wants to promote greater awareness of the oceans and the planet.
He said he is brimming with confidence despite his taekwondo tournament in Rio in 2016 ending quickly with a 16-1 thrashing in his first match.
He also finished 114th out of 119 in his cross-country race in Pyeongchang.
Prannoy stuns Sugiarto, Sai Praneeth crashes out of NZ Open
India's HS Prannoy stunned Tommy Sugiarto in straight games to sail into the men's singles quarter-finals even as compatriot B Sai Praneeth crashed out in the second round of the New Zealand Open badminton tournament.
Unseeded Prannoy shocked second seed Sugiarto 21-14, 21-12 in just 37 minutes to book a place in the last-eight round, where he will be up against fifth seed Kanta Tsuneyama of Japan.
This was world No. 26 Prannoy's maiden meeting with world No. 13 Sugiarto.
Earlier in the day, Praneeth suffered a straight-games 12-21, 12-21 loss to the legendary Lin Dan of China.
Seventh seed Lin Dan, thus, progressed to the quarter-finals, where he will be up against top seed Anthony Sinisuka Ginting of Indonesia.
India's men's doubles pair of Manu Attri and Sumeeth B Reddy too lost in the second round, going down to seventh seeds Goh V Shem and Tan Wee Kiong of Malaysia 17-21, 19-21
London Olympics bronze medallist Saina Nehwal on Wednesday made a first round exit from the women's singles after being stunned by to world No. 212 Wang Zhiyi of China.
In the match between Prannoy and Sugiarto, the Indian seized the initiative early on and took a 7-3 lead before extending it to 11-4.
From there on, it was no looking back for Prannoy as he went on to maintain his lead all throughout and close out the game at 21-14.
It was neck and neck between the two shuttlers in the first few points of the second game. In fact, Sugiarto took the initial lead at 4-2 but Prannoy came back strongly to not only level the scores but surge ahead with four consecutive winners to take a 8-4 lead.
Once Prannoy took the lead, he did not look back and kept maintaining the gap to seal the contest.