Tomas Berdych defeated Stanislas Wawrinka in a battle of Davis Cup marathon men on Sunday as defending champions Czech Republic moved into the quarter-finals.
The Czechs led Switzerland 2-1 overnight in Geneva after Berdych and Lukas Rosol beat Wawrinka and Marco Chiudinelli 6-4, 5-7, 6-4, 6-7 (3/7), 24-22 in the longest-ever Davis Cup match, an exhausting doubles which a minute over seven hours.
World number six Berdych and Wawrinka, the 17th-ranked player, returned on Sunday for the first of the reverse singles and three hours 15 minutes later it was the Czech who triumphed again, claiming a 6-3, 6-4, 3-6, 7-6 (7/5) win.
"Stan is one of the players who I don't like to play. He has a dangerous game," said Berdych, of a player who also featured in a five-hour defeat to Novak Djokovic at the Australian Open last month.
The Czech Republic will now travel to Kazakhstan in April for the quarter-finals for their second meeting with the former Soviet nation.
The Kazakhs, who beat Austria 3-1 in their World Group clash on Sunday in Astana, knocked the Czechs out in the first round in 2011 when they squeezed out victory in the deciding rubber.
Later Sunday, five-time champions Spain will look to overturn a 2-1 deficit and beat Canada.
Marcel Granollers and Marc Lopez kept the injury-depleted Spaniards' hopes alive as they battled to a 4-6, 6-4, 6-7 (4/7), 6-3, 6-2 victory over Daniel Nestor and Vasek Pospisil in Vancouver on Saturday.
Missing top players Rafael Nadal, David Ferrer, Nicolas Almagro and Fernando Verdasco, Spain still face an uphill task.
Granollers, the world number 34 who was beaten in straight sets by 166th-ranked Frank Dancevic on Friday, will have to dig deep to find the energy to take on Canada's world number 15 Milos Raonic, while Dancevic will take on Albert Ramos.
The winners of that tie will meet either Italy or Croatia, who were standing at 2-2 in Turin, in the last eight.
Italy had led 2-1 overnight but Marin Cilic won his second singles of the tie by easing past Andreas Seppi 6-3, 6-3, 7-5.
Fabio Fognini will tackle Ivan Dodig later Sunday in the decisive rubber.
The United States, a record 32-time champions, are 2-1 ahead of Brazil in Florida after squandering the chance to wrap up the tie on Saturday when Bob and Mike Bryan suffered a stunning loss in the doubles.
Marcelo Melo and Bruno Soares claimed a famous 7-6 (8/6), 6-7 (7/9), 6-4, 3-6, 6-3 win to keep Brazil alive and condemn the American brothers to only the third defeat of their Davis Cup partnership.
The winners of that tie will meet 2010 champions Serbia who took an unassailable 3-0 lead over Belgium on Saturday.
The other quarter-final will see Argentina facing France after they also completed victories on Saturday.