He won the 4x400m relay gold medal at the 2003 World Championships in Paris, France.

He was the bronze medalist in the 400 metres hurdles at the 2004 Olympic Games in Athens, Greece.

He worked for six months as a postman, before stopping to focus his energies on the World Championships and Olympic Games.

Keïta tested positive for a prohibited substance (testosterone) while taking part in the 2007 World Athletics Championship in Osaka, Japan.

He was suspended from all competitions for two years by the Fédération française d'athlétisme in October 2007, with the suspension taking effect from 1 Sep 2007.