‘Photoshopping your back muscles’: Novak Djokovic trolls semi-naked tennis ace Karen Khachanov

Serbian tennis ace Novak Djokovic has mocked his Russian counterpart Karen Khachanov, leaving a humorous comment under an Instagram photo of him proudly displaying his back muscles.

The 23-year-old Russian shared a photo from his Maldives vacation of him posing semi-naked in a swimming pool with his back to the camera and showing off his perfectly-built muscular body.

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Just chilling and nothing more,” Khachanov captioned the snap, which didn’t go unnoticed by tennis icon Djokovic.

The 16-time Grand Slam winner left a comment on Khachanov’s post joking that the player had enlarged his muscles with the help of photo editing software.

Photoshopping your back muscles man…come on,” he wrote.

Last week, Djokovic won the Rolex Paris Masters 1000, defeating Canadian youngster Denis Shapovalov 6-3, 6-4 in the final.

He is now taking part in the Nitto ATP Finals in a bid to reclaim the status of year-end number one from Rafael Nadal, who again tops the men’s rankings.