Michael Phelps won the 17th Olympic gold medal of his career, and his 21st overall, when he produced a majestic performance in the 100m butterfly.

Michael Phelps claimed his second individual gold medal at the World Championships as he retained his 100 metres butterfly crown in Shanghai.

The Court of Arbitration for Sport has confirmed the hearing into the punishments handed to four Brazilian swimmers for failing drugs tests will take place before the World Championships later this month.