Australian rivals Bernard Tomic and Nick Kyrgios met at the Kooyong Classic, with Tomic claiming a straight-sets win with a cheeky between-the-legs serve that left his opponent stunned.
Former US Open champion Cilic, who led Croatia to a Davis Cup trophy in November, skipped last week's Maharashtra ATP tournament to rest.
US Open quarter-finalist John Millman plays Argentine Federico Delbonis.
In this instance, the ball did seem to touch the ground before it was hit.
The World No 83's good-natured 6-3, 6-4 victory over his longtime friend Kyrgios ended with a flourish when he sent down the sneaky serve while bouncing another ball, on match point.
Yet both players have maintained their off-court clashes of the past - notably almost three years ago when Tomic accused Kyrgios of faking an illness to get out of playing a Davis Cup match - are behind them, and considering the relaxed nature of this tournament, it's unlikely sparks will fly when the pair finally do face off across the net.
"I want to be as healthy and fresh as possible heading into next week".More news: Marko Arnautovic Wants To Leave West Ham For China
The Australian's ranking is up to No. 85 in the world just ahead of his home Slam, while Kyrgios has dipped down to No. 51.
Kyrgios, who lost in the second round at the Brisbane International last week, had a break point early in the second but was unable to consolidate with Tomic then breaking at 3-3.
"I'm not entirely sure what I will be doing but I think there will be more things on than the Australian Open draw", he said with a laugh.
It was a fitting ending however for a rather tiresome contest, with Kyrgios struggling from the outset as Tomic lulled his rival into his game plan.
"Definitely I struggled with a lot of things past year, my body was one and I was going through some tough times", Kyrgios said.
"It was good to get out on court. I know it was just an exhibition, but he was pretty impressive". "But at the moment I'm happy, the last three months (of 2018) was good".