They don't call him "Djoker" for nothing.

Novak Djokovic, the second seed at this month's U.S. Open, has proven that he is willing to let loose and have some fun. Djokovic's lighter side was on display recently during a practice round at the U.S. Open.

While the Serbian was taking some serves, a young fan yelled out from the stands: "Djokovic, will you marry me?" The crowd burst into laughter, and Djokovic was clearly amused. He invited the youngster to the court and offered his racquet.

The kid took a few serves, and Djokovic raced over to field the balls barehanded. Overall, a very nice gesture by the Djoker.

The proposal occurs at the :26 mark.

One year after dominating the circuit, Djokovic has struggled recently. He was ousted in the semifinals of both Wimbledon and the Olympics. So it's nice to see that even before a crucial tournament, he's still able to have some fun.

Follow us on Facebook and Twitter to read them first!

1962 Porsche Becomes BBQ Grill