By Mitch Phillips
Hot favourite Caster Semenya qualified for the Olympic women's 800metres semi-finals with supreme ease on Wednesday and will no doubt be braced for another wave of discussions about her gender should she go on to take the gold medal on Saturday.
The South African has dominated the event this season and there has even been speculation that she could take down Czech Jarmila Kratochvilova's 1983 record of 1 minute, 53.28 seconds - the longest standing athletics world record and widely considered to have been chemically enhanced.
Many observers consider Semenya to be also running with an unfair advantage, albeit one she can do little about.
After winning the 2009 world title as a 19-year-old, tests by the sport's governing body are reported to have revealed that Semenya was hyperandrogenous, resulting in her body producing an abnormally high amount of testosterone which makes her more powerful than her rivals.
An International Association of Athletics Federations (IAAF) rule limiting the amount of naturally occurring functional testosterone for female athletes appeared to have brought an end of Semenya's career, but the rule was quashed by the Court of Arbitration for Sport last year.
Semenya had struggled to rediscover the form of her breakthrough year - some observers blaming the dip on medication to reduce the testosterone - but this season she has roared back to her best and came to Rio with the two fastest times of the year and unbeaten on the Diamond League circuit.
IAAF president Sebastian Coe said last week that his organisation was planning an appeal against the CAS ruling, so this week could turn out to be Semenya's last chance for Olympic glory following her silver medal four years ago.
She won her heat in 1.59.31 and, though it looked as if she was enjoying a Sunday morning jog in the park, she said it was harder than she made it appear.
"It wasn't easy, It was pretty hot," she said. "I just tried to hang on and tried to feel my body first so I was comfortable, I tried to just get in the top two and tried to win so I would be safe for the semi-finals.
"I am not focused on any world records, I am focused on enjoying my championship and it's going to be a tough 800. Times don't matter but medals matter."
Belarusian Maryna Arzamasava and Canada's Melissa Bishop, first and second in last year's world championships, found themselves in the same heat but took both automatic qualifying spots for Saturday's final with the two fastest times of the day, just under a second quicker than Semenya.
Russian duo Mariya Savinova and Ekaterina Poistogova, first and third in the race in London four years ago, were unable to take part in Rio due to the doping ban on the country's athletes.