Croatian tennis player Marin Cilic has been given a nine-month ban for doping by the International Tennis Federation.

He tested positive for nikethamide - a stimulant - at an event in Munich earlier this year.

An independent tribunal found that Cilic took the substance inadvertently as a result of taking glucose tablets.

The suspension has been back-dated to the first of May, meaning that the Croatian has to pay back any prize-money earned since then.

He will not return to action until February 1, 2014.

Cilic reached the Australian OPen semi-final in 2010 and has twice appeared at the US Open quarter-finals.