AFP - Rafael Nadal battled back from a set down to defeat brave Argentine Juan Martin del Potro and hand Spain a fifth Davis Cup title on Sunday.
In the same Olympic stadium where the world number two became the youngest Davis Cup winner in 2004, Nadal saw off Del Potro 1-6, 6-4, 6-1, 7-6 (7/0) in a little over four hours to give the hosts an unassailable 3-1 lead.
"It was a very emotional match and I am happy for the team," said Nadal, who has now won 20 of his 21 singles rubbers for Spain, but had never before claimed the winning point.
His only loss came to Czech Jiri Novak on his debut -- as a 17-year-old -- in February 2004.
"It was the most amazing atmosphere I have ever played in. The crowd were crazy. Everything was perfect," added the French Open champion of the electric atmosphere generated by 25,000 fans.
"It was complicated at the start of the match, but the beginning of the second set was very important and at 1-0 and 40-0 that was the turning point for me.
"Delpo was playing amazingly today, especially the flat shots, it was really hard"
Sunday's win followed titles for Spain in 2000, 2004, 2008 and 2009, meaning all of their wins have come in the space of 11 years.
"It was an unbelievable match. These guys are great and that's why we were in the final," said Spanish captain Albert Costa.
"Rafa tried to play deeper and harder because at the start Del Potro was inside the line and hitting so hard. He fought hard so that's why we won."
Nadal and David Ferrer had won Friday's opening singles before David Nalbandian and Eduardo Schwank kept Argentina's hopes alive by beating Feliciano Lopez and Fernando Verdasco in Saturday's doubles.
It was more heartbreak for Argentina who became the first nation to lose four finals -- they also lost to Spain in the final three years ago at home.
"Spain, playing on clay, as a home team -- this is one of the best teams in history," admitted Argentina captain Tito Vazquez.
Del Potro, who lost a marathon five setter to Ferrer on Friday, had gotten off to a strong start leading 6-1, 1-0 and 40-0 on his service against Nadal.
But Nadal hung on to get back into the match as Del Potro began to show signs of the fatigue from Friday's five-hour marathon playing with both of his thighs bandaged.
Despite looking dead and buried after losing his serve early in the fourth set, Del Potro managed to claw his way back into the tie with some magical shots which saw him serve for the set at 5-3.
Nadal dug deep however and the momentum swung his way again and once into the tie-break there was no looking back as he sealed victory with a winning forehand.
The victory capped the season for Nadal after a difficult six months since winning Roland Garros in June.
Spain still some way to go to match the leading winners in Davis Cup history.
The United States lead the way with 32 wins with Australia in second place with 28.