Caster Semenya (Getty Images)
Rio de Janeiro - One of the biggest stories of the Rio Olympics begins on Wednesday when Caster Semenya takes to the track for the first time.
Semenya is the overwhelming favourite to win the women's 800m final on Sunday and she will run her heat at 16:02 (SA time) on Wednesday.
But on the eve of what is the biggest week of Semenya's life, the debate surrounding testosterone levels in female athletes has gained more momentum than ever after IAAF president Sebastian Coe last week questioned the merits of a Court of Arbitration for Sport (CAS) decision taken in July 2015 that put a stop to testosterone regulation in female athletes.
Semenya, who has been at the centre of a gender testing controversy since 2009, will as a result be the centre of attention as the 2016 Olympics winds down.
The fear is that the main focus will not be on what she achieves on the track.
Journalists from all over the world will line up in their numbers looking for a line from the 25-year-old and it is understood that her media engagements will be kept to a minimum over the next few days.
Semenya wants to run, and win. But the next few days will be about much more than that.
How the Brazilian spectators, who have not always been the most respectful bunch over the past 10 days, respond to Semenya is also going to be telling.
The athletics stories of the Games so far have all been positive ... Wayde van Niekerk, Usain Bolt, Thiago Braz da Silva all stealing headlines for the right reasons.
If Semenya dominates as expected, then her story will command as much attention - and maybe more - than any of those.
How that story will be told, and remembered, is where it all gets a bit tricky ...