Gold medal favourite banned from Olympics after positive marijuana test

American champion Sha'Carri Richardson cannot run in the Olympic 100-metre race after testing positive for a chemical found in marijuana.

BBC News reports Richardson who won the 100 metres at the US Olympic trials in 10.86 seconds on June 19, spoke of her ban today on the “Today" show.

She tested positive at the Olympic trials so her result is erased.

Fourth-place finisher Jenna Prandini is expected to get Richardson's spot in the 100.

Richardson accepted a 30-day suspension that ends July 27, which would be in time to run in the women's relays.

The 21-year-old sprinter was expected to face Jamaica's Shelly-Ann Fraser-Pryce in one of the most highly anticipated races of the Olympic track meet.

[Source:  BBC]