Semenya runs fastest 400 metres of year to give Olympic hope

Caster Semenya competes in this picture taken March 22, 2016. Athletics - ASA After Dark meeting Ð women"s 800m run - Green Point Stadium, Cape Town,

Caster Semenya laid down a marker in the race for 400 metres gold at the Rio de Janeiro Olympics in August by running the fastest time of the year at the South African Championship on Saturday.

She clocked 50.76 seconds, eclipsing the previous 2016 best of 50.91 by American runner Jaide Stepter registered in Los Angeles last month.