Injury-plagued Thanasi Kokkinakis has been forced to withdraw midway through his Australian Open first-round match against Japan’s Taro Daniel due to a shoulder problem.

Kokkinakis won the first set of his clash against Daniel 7-5 on Tuesday before calling a medical timeout early in the second set to receive treatment on his right shoulder.

Clearly in duress, the Australian battled for another few games before finally calling a halt to the match with Daniel leading 4-2 30-0 in the second set.