David Nalbandian and Jose Acasuso beat Ivan Ljubicic and Marin Cilic 6-4 6-2 3-6 6-4 in Saturday's doubles to give Argentina a 2-1 lead over holders Croatia in their Davis Cup quarter-final.
The Argentines capitalised on Mario Ancic's back injury and a subdued performance by his replacement Cilic, who made a number of unforced errors in the opening two sets.
The 17-year old, who was outclassed in straight sets by Nalbandian in Friday's opening singles rubbers after standing in for Ancic, improved in the third set but failed to hold his serve in the final game of the fourth after committing two unforced errors.
Ljubicic, the world number five and Croatia's team captain, must beat world number three Nalbandian in the opening reverse singles on Sunday to keep the defending champions in the competition.
Ancic has been nominated to play Agustin Calleri in the final rubber if he recovers from a back problem sustained in Wednesday's practice. Either Cilic or Sasa Tuksar will replace Ancic if he is ruled out.
The winners of the tie will face Australia in the semi-finals.
