PHOTO: Novak Djokovic playing with his adorable son Stefan!

New Delhi: World No. 1 Novak Djokovic, who won his 10th Grand Slam title by winning the US Open 2015, on Wednesday shared a photograph where he can be seen playing with his son Stefan.

Djokovic, who defeated Roger Federer in four sets, posted the photo on his Facebook page.

A little post tournament hang time with my boy :) He says just the right things to make a wonderful day even better!...

Posted by Novak Djokovic on Tuesday, 15 September 2015

Djokovic became a father for the first time last year in October when his wife Jelena Djokovic gave birth to their baby boy.

The 28-year-old Serb had a tremendous 2015, where he reached the finals of all the four Grand Slams and won three.