Croatia and Argentina are locked at 1-1 after the first day of the Davis Cup final in Zagreb.
Marin Cilic survived Federico Delbonis' fightback in the first rubber before Juan Martin del Potro levelled the final with victory over Ivo Karlovic.
World number six Cilic beat 41-ranked Delbonis 6-3 7-5 3-6 1-6 6-2 in a five-set thriller, but Del Potro, the 2009 US Open champion, responded for the Argentinians by winning the second singles match against the big-serving Karlovic in four sets - 6-4 6-7 6-3 7-5.
Saturday's action at the Arena Zagreb sees Ivan Dodig and Franko Skugor face Argentinian pair Leonardo Mayer and Guido Pella in the doubles.
Croatia won the Davis Cup in 2005, while Argentina are aiming to improve on a record of four final defeats.
Source: PA
