Nick Kyrgios’ return to the Australian Open is over after he and Thanasi Kokkinakis stopped playing while trailing in the second set of their first-round doubles on Thursday night. Kyrgios and Kokkinakis, the men’s doubles champions at Melbourne Park in 2022, retired while down 7-5, 3-2 against another Australian team, James Duckworth and Aleksandar Vukic. Both Kyrgios (strained abdominal muscle) and Kokkinakis (right shoulder trouble) came into the match dealing with physical issues after losses in singles.