Reigning US Open Champion Marin Cilic defeated Kazakhstan's Mikhail Kukushkin 6-7, 7-6, 6-3, 6-7, 6-1 to sail into the fourth round of the US Open on Friday. Top-seeded Novak Djokovic also won his third round match against Italian Andreas Seppi 6-3, 7-5, 7-5 on Friday. Frenchman Jo-Wilfried Tsonga defeated Ukraine's Sergiy Stakhovsky 6-3, 7-5, 6-2 to enter the fourth round.