Debate - Does Caster Semenya Have an Unfair Advantage?

Potentially one of the most pivotal moments in modern sport will occur not on a track, pitch or court, but in a plush office building in the Swiss city of Lausanne on Wednesday.

The Court of Arbitration in Sport (Cas) is expected to announce a verdict on one of athletics' biggest names - South Africa's Caster Semenya - and her right to compete as a woman.

Caster Semenya is one of the most dominant stars of modern athletics.

A double Olympic gold medallist and three-time world champion over 800m, the 28-year-old South African has won her past 29 races over the distance.

However, since her meteoric rise from unknown teenager to world champion in 2009, her gender, and possible advantages in her biology, have come under scrutiny.

The results of gender testing carried out 10 years ago have not been made public, although media reports claimed it showed both male and female characteristics including a higher-than-normal level of testosterone.

Former Olympic swimmer Sharron Davies and transgender journalist India Willoughby debate.