What does the number one tennis player in the world, Novak Djokovic, do with his spare time off the court? Take funny photos of his long-time girlfriend, Jelena Ristic.

After his fourth-round win at the Australian Open on Monday, Djokovic told reporters and fans when pressed by Australia’s Channel 7 that before his match, he took comical pictures of his girlfriend Ristic using an app to make a person look fat by adding a few hundred pounds to their face.

Hours later, Djokovic posted the photo to his Twitter account for his more than half a million followers, much to Ristic’s amusement, according to Yahoo Sports.

Serbian star Novak Djokovic has been off the market since his career took off in 2005, dating girlfriend Jelena Ristic.

Ristic and Djokovic, who have been dating for more than five years, met through, you guessed it, tennis. The couple reportedly met through mutual friends in Serbia, according to the Wide World of Sports.

While not much is known about her aside from her studies in finance in Milan, Ristic seems to be Djokovic's biggest fan, attending all of his games.

In a video clip for the ATP World Tour, Jelena Ristic was photographed with Djokovic and paused to comment on her boyfriend's success.

I'm really proud. It's his dream to be so successful and I'm really happy for him that he managed to, you know, accomplish at least part of his dream, Ristic said. Hopefully I'll be there to help him and to see him achieving the biggest one, the top.