Chad Le Clos’s chances of winning three Olympic medals at the Rio Games next month just got a little bit tougher.

Korean doper Tae Hwan Park – a former two-times 400m freestyle world champion – on Friday won his case at the Court of Arbitration for Sport (CAS) in Switzerland‚ allowing him to be eligible for selection for the Brazilian showpiece.

This means Park could be another rival for Le Clos in the 200m freestyle‚ in which the Korean has won Olympic silver medals at the past two Games.

The South African star is a favourite to win medals in the 100m and 200m butterfly‚ the events in which he made the podium at London 2012.

But this time he’s likely to add the 200m freestyle to his repertoire.

He finished sixth in this event at last year’s world championships‚ but has since said he has improved vastly.

Park was banned for 18 months after testing positive for testosterone‚ and the suspension ended on March 2 this year.

Korean Olympic Committee (KOC) regulations‚ however‚ prohibit an athlete competing for the national team for three years from the completion of a doping sanction.

In a statement on Thursday‚ CAS said it had upheld a request “for provisional measures filed by … Park … in the course of his arbitration procedure” with the [KOC] and Korean swimming federation.

“The decision … means that he is eligible to be selected to swim for the Korean team in the Rio 2016 Olympic Games.”