Djokovic withdraws, Argentina into Davis Cup final

By the Associated Press | September 18, 2011 | 10:30 AM EDT

Novak Djokovic of Serbia stretches his back during his World Group Davis Cup semifinals tennis match against Juan Martin Del Potro of Argentina in Belgrade, Serbia, Sunday, Sept. 18, 2011. (AP Photo/ Marko Drobnjakovic)

BELGRADE, Serbia (AP) — Novak Djokovic withdrew from his match because of back pain, giving Argentina an insurmountable 3-1 lead over Serbia to reach the Davis Cup final.

The top-ranked Serb fell to the floor Sunday with back pain during the third game of the second set after losing the first set to Martin Del Potro 7-6 (5).

Argentina will play Spain in the final.

Rafael Nadal put Spain into the final after routing Jo-Wilfried Tsonga 6-0, 6-2, 6-4 for an insurmountable 3-1 lead against France in the other semifinal.