Djokovic said: "I got this mask at dinner (three years ago). I asked them, Can I take it? They allowed me to take it. The next day I say for fun I'm going to get into the court like that. I did. That's a little tradition I have with the mask at Halloween."In that match, Tursunov retired with a shoulder injury. Djokovic was ahead of the match with 6-2, 4-3.
(Via Yahoo! Sport)