Novak Djokovic took a break on his day off from the US Open on Wednesday by heading out to dinner in Brooklyn. The World No. 1, his girlfriend, Jelena Ristic, and a group of friends were spotted at Antica Pesa in Williamsburg, where we’re told the Serbian superstar drank only water and surprised the staff by speaking fluent Italian and insisting on going into the open kitchen to thank everyone. “It was really nice of him,” said an awed onlooker, who added he took photos with all.