Argentina battled back to beat Croatia 3-2 and win the Davis Cup without precedent for an emotional last in Zagreb.
Croatia drove 2-1 going into the last day and looked on course for their second title when Marin Cilic drove Juan Martin del Potro by two sets to love.
Be that as it may, Del Potro organized an exceptional rebound to win 6-7 (4-7) 2-6 7-5 6-4 6-3 in four hours 53 minutes.
Federico Delbonis then cleared past Ivo Karlovic 6-3 6-4 6-2 in the unequivocal fifth challenge to secure triumph.
Argentina had lost in four past finals at the same time, thundered on by a vociferous 1,500-in number gathering of voyaging fans that included 1986 World Cup victor Diego Maradona, the guests secured a dazzling win.
Del Potro set the victors on their way from an apparently frantic circumstance at two-sets down to world number six Cilic.
The triumph topped an astounding year which has seen the 28-year-old come back from four wrist surgeries to win Olympic silver and beat any semblance of Novak Djokovic, Stan Wawrinka and, in the quarter-finals of the Davis Cup, Andy Murray.
“This was an emotionally exhausting match and one of the biggest wins of my career,” said Del Potro.
“Thanks to all those who prevented me from retiring; I was very close to never playing again and, well, here I am.”
Argentina captain Daniel Orsanic added: “His comeback is the comeback of history, his comeback today was the comeback of the Davis Cup.
“He’s a genius. His heart is so big.”
Delbonis is positioned 21 puts beneath Karlovic at 41 on the planet however splendidly gave back the 6ft 11in Croat’s colossal serve.
“He was on top of every ball,” said Orsanic. “He played a perfect match. I’m surprised, in a good way. I thought he couldn’t win so easy.”
Davis Cup final result: Croatia 2-3 Argentina
Friday: Marin Cilic (Cro) beat Federico Delbonis (Arg) 6-3 7-5 3-6 1-6 6-2
Juan Martin del Potro (Arg) beat Ivo Karlovic (Cro) 6-4 6-7 (6-8) 6-3 7-5
Saturday: Marin Cilic & Ivan Dodig (Cro) beat Juan Martin del Potro & Leonardo Mayer (Arg) 7-6 (7-2) 7-6 (7-4) 6-3
Sunday: Juan Martin del Potro (Arg) beat Marin Cilic (Cro) 6-7 (4-7) 2-6 7-5 6-4 6-3
Federico Delbonis (Arg) beat Ivo Karlovic (Cro) 6-3 6-4 6-2