Kraljevo, Serbia (SportsNetwork.com) - Novak Djokovic was inserted into the doubles lineup Saturday and helped Serbia clinch a spot in the Davis Cup quarterfinals.

Djokovic easily won his opening singles match Friday to help the hosts to a 2-0 lead over Croatia in the first round of the Davis Cup, but was not originally slated to play Saturday.

However, after Viktor Troicki went five sets to rally past Borna Coric in Friday's second singles match, a fresher Djokovic was called upon to take the court with Nenad Zimonjic. The duo rolled to a 6-3, 6-4, 6-1 triumph over Franko Sjkugor and Marin Draganja to wrap up the best-of-five tie.

Serbia owns an insurmountable 3-0 advantage and will next play against the winner between Argentina and Brazil in July's quarterfinals.

Djokovic had a relatively easy couple of matches this weekend. He powered past Mate Delic on Friday in a 6-3, 6-2, 6-4 rout to give the hosts the first point.

Serbia won its lone Davis Cup title in 2010, beating Croatia en route to the crown, and was the runner-up two years ago.