Grumbling and muttering on court amid his second-set pummelling, the mercurial Australian cut a disgruntled figure by the end of the drubbing on Friday, yet afterwards he was still putting on a brave face following his second match in three days in his latest injury comeback.
"Honestly today was a big stepping stone. @karenkhachanov was just too good. We played a great first set but encouraging that I could finish 2 matches this week!" tweeted Kyrgios on X.
The Canberran had admitted he'd no idea how his injury-prone racquet wrist would pull up after his encouraging first-round victory over Mackenzie Macdonald, his first tour-level victory in two-and-a-half years.
But the Hard Rock Stadium crowd soon found out on Friday as Kyrgios began by going punch-for-punch with one of the world's best, only to wholly run out of steam - and, seemingly, belief - as he delivered a dismal second-set performance in which he mustered just seven points.
In an odd performance which showed off the familiar Jekyll-and-Hyde faces of the former Wimbledon finalist, there was much to applaud about the way Kyrgios mixed it with the Russian 22nd seed, taking Khachanov to a tiebreak in a feisty opening-set display.
But after he missed a chance to go 3-1 up in the tiebreak, making a mess of a forehand and allowing Khachanov take control, it was as if he became a different player, perhaps recognising that to win two more sets was going to be a mountain too high to climb in his physical state.
Sure enough, Khachanov began to bully him, with Kyrgios just getting more irritated with himself and his team at courtside, offering a running commentary on everything that was bothering him, which appeared to include a problem with his shoulder.
He smashed one ball high out of court to earn a warning from the chair umpire as the ferocity of his first-set hitting gave way to casual, sloppy strokemaking.
When he hit a forehand long, his 30th unforced error, he was eventually put out of his misery, the second set having lasted just 21 minutes, compared to the first which had been nearly an hour-long battle.
Still, it was a performance that offered just a tantalising glimpse of the brilliance Kyrgios can still produce against a player of the quality of world No.23 Khachanov, who was his last opponent in a grand slam back at the US Open in 2022 when the Russian won a much more competitive affair.
Another Australian Rinky Hijikata also suffered a 'bagel' set before showing some real grit in a 6-0 7-6 (7-1) defeat by a rejuvenated Novak Djokovic, who ended a rare three-match losing streak with an impressive display en route to equalling Rafa Nadal's all-time record of 410 Masters 1000 wins.
The 24-time grand slam champ, who hadn't won a match since his injury exit in the Australian Open semi-final, described his first-set tennis as "almost flawless" but was full of praise for the Sydneysider "stepping up and producing some higher quality tennis" in the second.
Perth qualifier Tristan Schoolkate had earlier also gone out at the second-round stage, beaten by Canadian Felix Auger-Aliassime 6-4 6-4.
14°C