article_snippet: Serbia's No 1 celebrates after leading Viktor Troicki past Croatia and into the Davis Cup quarter finals .
article_snippet: Serbia's No 1 played a major role in Viktor Troicki 's victory, beating Mate Delic in singles before teaming up with Nenad Zimonjic to beat Marin Draganja and Franko Skugor in the doubles.
article_snippet: Novak Djokovic, though, wasn't even initially supposed to play in the match.
article_snippet: Viktor Troicki was named to play alongside Nenad Zimonjic but Serbia coach Bogdan Obradovic opted for Novak Djokovic after Viktor Troicki impressive performance against Mate Delic.
article_snippet: Serbia players celebrate after setting up a Davis Cup showdown with Argentina .
highlights_snippet: Novak Djokovic helped Serbia past Croatia into Davis Cup quarter finals .
  