Sprinter Tyson Gay is heading back to the Olympics, more than two years after a failed doping test cost the Americans their 2012 relay medal.

Gay crashed out at the US Olympic trials in individual events, finishing fifth in the 100 and sixth in the 200.

But he's been selected in a six strong sprint relay pool for Rio.

Gay returned a positive test in 2013, meaning his silver medal in the 4x100m relay in London was stripped.