Thanasi Kokkinakis concedes his debilitating pectoral muscle injury will likely force him to pull out of his hotly-anticipated 'Special Ks' doubles reunion with Nick Kyrgios.

Australian doubles pair James Duckworth and Aleksandar Vukic have eased into the second round of the men's doubles after opponents Nick Kyrgios and Thanasi Kokkinakis retired during the second set of their match on John Cain Arena.

Thanasi Kokkinakis succumbed to injury as he and Nick Kyrgios withdrew from their Australian Open doubles match against James Duckworth and Aleksandar Vukic.

Injury-riddled Thanasi Kokkinakis and Nick Kyrgios were forced to retire early in their men's doubles reunion at Melbourne Park after a set and a half.

Nick Kyrgios and Thanasi Kokkinakis are back in the Australian Open men's doubles draw for the first time since winning the title in

Kokkinakis has been struggling with a pectoral injury for some time, and was forced to withdraw from the Adelaide International last week. He managed to win his first-round singles match at the Australian Open, before suffering a heartbreaking five-set loss in the second round.

It was a miracle that they were even out there, but in the end a win was too much to ask of Thanasi Kokkinakis and Nick Kyrgios, who were unable to overcome their Aus Open injury issues. The first miracle came when Nick Kyrgios and Thanasi Kokkinakis produced Lazarus-like recoveries from their respective death beds to appear at John Cain Arena for their opening round doubles match.

The apologetic Aussie was plainly ‘shattered’ to tell his great mate Nick Kyrgios it was all over. Thanasi Kokkinakis’ dream of repeating his stunning Australian Open doubles success with Nick Kyrgios has been dashed by his debilitating pectoral muscle injury.