ZAGREB, Croatia (AP) Croatia won the opening singles of the Davis Cup final after Marin Cilic struggled past Argentina's Frederico Delbonis 6-3, 7-5, 3-6, 1-6, 6-2 on Friday.
Cilic, the 2014 U.S. Open champion, looked like cruising to the expected easy victory until Delbonis broke the Croat twice in the third set, which ended on a Cilic double fault.
Delbonis started the fourth 3-0 with a double break, and Cilic conceded the set on serve by netting an easy smash.
But after a bathroom beak, Cilic came back renewed and broke Delbonis to start the fifth set on the indoor hard court at Arena Zagreb. Cilic suddenly rediscovered his serving groove, and didn't give Delbonis a chance.
Cilic broke again in the seventh game, and served out after 3 1/2 hours, two hours longer than most expected.
Ivo Karlovic was playing Argentina's Juan Martin del Potro, the 2009 U.S. Open champion, in the second singles.
Croatia is targeting its second Davis Cup title, and Argentina its first.
