Nick Kyrgios' return to the Australian Open is over after he and partner Thanasi Kokkinakis stopped playing while trailing in the second set of their first-round doubles match.

World No 1 Jannik Sinner makes it 16 wins in a row; No 5 seed Daniil Medvedev dumped out of Australian Open by 19-year-old American Learner Tien in five-set epic; Nick Kyrgios and Thanasi Kokkinakis p

Australian tennis star Thanasi Kokkinakis has stunned his opponent with an amazing act of sportsmanship at a critical moment of their second-round Australian Open clash. British No.15 seed Jack Draper was serving at two sets to one down, and trailing by a break in the fourth when he was about to be denied a certain point after a long rally.

Kokkinakis was forced to withdraw from the Adelaide International last week due to a shoulder injury, and his chances of a first-round win at the Australian Open looked dire. It led Aussie legend Woodbridge to question whether Kokkinakis should have been prioritising rest in the lead-up instead of playing exhibition events for the money.

Nick Kyrgios' Australian Open farewell could be at risk after his doubles partner, Thanasi Kokkinakis, raised concerns about his fitness to compete in their opening match in Melbourne.