Bob and Mike Bryan beat Marcel Granollers and Marc Lopez 6-3, 3-6, 7-5, 7-5 on Saturday as the United States stayed alive in their Davis Cup semi-final against defending champions Spain.
Trailing 2-0 overnight on the clay courts of Gijon, the Olympic and US Open champions secured a crucial point which will mean the tie will be decided on Sunday with a place in November's final at stake.
Saturday's rubber lasted three hours 38 minutes as the Bryans took their Davis Cup record to 20-2.
"They're pretty good in the clutch and they get us to Sunday when we're in this position all the time. We've got a chance," said US captain Jim Courier.
Five-time champions Spain are defending a run of 23 consecutive home victories in the tournament, a streak stretching back to 1999.
They had edged closer to a sixth final in 10 years on Friday when they shrugged off the absence of Rafael Nadal to open a 2-0 lead.
World number five David Ferrer beat Sam Querrey 4-6, 6-2, 6-2, 6-4 before Nicolas Almagro won a four-hour slog against John Isner, 6-4, 4-6, 6-4, 3-6, 7-5.
On Sunday, Ferrer will face Isner in the first reverse singles with Almagro scheduled to meet Querrey.
"Ferrer is such a warrior and a great competitor and John's going to have to play better than he did yesterday to stand a chance. He's a little bit more physically taxed than David is for sure," added Courier.
In Buenos Aires, Tomas Berdych and Radek Stepanek eased past Carlos Berlocq and Eduardo Schwank 6-3, 6-4, 6-3 to give the Czech Republic a 2-1 lead over Argentina in the other semi-final.
The Czech duo claimed victory after two hours and 37 minutes at a shell-shocked Parque Roca to take their Davis Cup record to 11-1.
"It's very loud in here and we knew that when we were coming to this place," said Stepanek.
"It was always going to be like that so we concentrated only on our half of the court. We said before the match, we play the match together and we are partners and stick together all the way no matter what."
Juan Martin Del Potro, the world number eight, defeated Stepanek 6-4, 6-4, 6-2 in the first singles rubber on Friday before Berdych, a US Open semi-finalist, levelled the semi-final, beating Juan Monaco 6-1, 4-6, 1-6, 6-4, 6-4.
On Sunday, Del Potro is expected to recover from his wrist injury in time to face Berdych in the first of the reverse singles with Monaco scheduled to tackle Stepanek.
In the play-offs, where victory assures a place in the World Group for 2013, the Netherlands stayed in contention against Switzerland in Amsterdam when Robin Haase and Jean-Julien Rojer stunned Roger Federer and Stanislas Wawrinka 6-4, 6-2, 5-7, 6-3.
Federer and Wawrinka, who were doubles gold medallists at the 2008 Olympic Games, had both won their singles on Friday to give the Swiss a 2-0 lead.
The tie will be decided on Sunday when world number one Federer tackles Haase, the world 41, in the opening reverse singles, before Wawrinka takes on Thiemo de Bakker.
"It won't be an easy job but I will give it everything against Roger," said Haase.
"It's cold, the clay is heavy. I know he won't like that."
Belgium were promoted to the World Group after Olivier Rochus and Ruben Bemelmans beat Sweden's Michael Ryderstedt and Johan Brunstrom 6-4, 4-6, 6-3, 6-2 for an unassailable 3-0 lead in Brussels.
The result means Sweden will not feature in the World Group for the first time since 2000.
In Hamburg, Lleyton Hewitt and Chris Guccione enjoyed a 6-3, 6-2, 2-6, 7-6 (7/4) victory over Benjamin Becker and Philipp Petzschner to give Australia a 2-1 lead over Germany.
Jonathan Erlich and Andy Ram claimed a 5-7, 6-3, 6-3, 6-1 win over Tatsuma Ito and Yuichi Sugita to give Israel a 2-1 lead over Japan in Tokyo.
Elsewhere, Italy lead Chile 2-1 in Naples, Kazakhstan are 2-1 up on Uzbekistan in Almaty, Canada led South Africa 2-0 overnight in Montreal while Brazil opened a 2-0 advantage over two-time champions Russia in Sao Jose do Rio Preto.