BELGRADE, Serbia — Serbia has knocked the U.S. out of the Davis Cup with Novak Djokovic outlasting John Isner 7-5, 3-6, 6-3, 6-7(6), 6-4 to give Serbia an insurmountable 3-1 lead in the first-round match.

Djokovic's victory on Sunday came after Isner and Bob Bryan got the U.S. within 2-1 by defeating Nenad Zimonjic and Janko Tipsarevic in doubles Saturday.

Viktor Troicki defeated Isner in the opening singles on Friday and Djokovic beat Sam Querrey to give Serbia a 2-0 lead.

Serbia will play its quarterfinal match against Croatia.