Courting: Tennis bad boy Nick Kyrgios spotted kissing Russian beauty Kalinskaya after retiring from tournament in Mexico (PHOTOS)

Aussie bad boy Nick Kyrgios has been spotted kissing rising Russian tennis star Anna Kalinskaya in Acapulco, setting off more rumors of a budding romance between the pair.

The firebrand Aussie, dubbed a “bad boy” for his controversial on-court tantrums, was caught planting a kiss on Kalinskaya’s forehead in Mexico, triggering more talk that the couple might be dating.

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Photos shared on social media show the 24-year-old Australian hanging out with the Russian tennis star, 21, as they were eating tacos.

Kyrgios was seen with Kalinskaya just two days after he withdrew from his first-round match against Frenchman Ugo Humbert in Acapulco, where he was booed off court by fans.

The Aussie hot-head accused the Mexican crowd of “disrespect,” saying he had been forced to retire due to a wrist injury.

Kyrgios and Kalinskaya were rumored to be dating last year after the Aussie was spotted cheering for the up-and-coming Russian during the 2019 Citi Open in Washington.