BUENOS AIRES, Argentina (AP) Federico Delbonis defeated Viktor Troicki 2-6, 2-6, 6-4, 6-4, 6-2 to give Argentina a 2-0 lead over Serbia in their Davis Cup quarterfinal on Friday.
Delbonis went two sets behind against the 20th-ranked Troicki but rallied to level before dominating the fifth set to help the Argentines take a commanding lead in the clay-court tie.
Carlos Berlocq and Diego Schwartzman will play Dusan Lajovic and Nenad Zimonjic in the doubles on Saturday with a chance to put Argentina in the semifinals.
Earlier on Friday, Leonardo Mayer defeated Filip Krajinovic 6-4, 6-2, 6-1 to give the hosts a 1-0 lead. The 22nd-ranked Mayer broke Krajinovic's serve at 5-4 to win the first set, then controlled the last two to secure the important opening win.
Argentina hasn't reached the Davis Cup semifinals since 2013, when it lost to the Czech Republic for the second straight time. The Argentines are still searching for their first Davis Cup title despite reaching the final four times.
The South Americans beat Serbia in their last meeting, in the 2011 semifinals.
Serbia, without Novak Djokovic in Argentina, last reached the semifinals in 2013, when it beat Canada but went on to lose the final to the Czech Republic.
Serbia won its lone Davis Cup title in 2010 in a final against France.
The winner this weekend will play either Belgium or Canada in the semifinals, which will take place Sept. 18-20. Host Belgium led 2-0 after the first day of play on Friday.