Belgium and Argentina set up a Davis Cup semifinal in September, while Britain took the lead against France, and Australia stayed alive in the quarterfinals on Saturday.
Belgium reached its first semis since 1999 when Ruben Bemelmans and Kimmer Coppejans won the doubles for an unbeatable 3-0 lead over Canada on clay in Ostend.
Bemelmans and his fifth different partner in Davis Cup, Coppejans, beat Daniel Nestor and Canada's own newcomer, Adil Shamasdin, 7-5, 3-6, 6-4, 6-3 in 2 1/2 hours. Coppejans, the Junior French Open champion three years ago, served out the last game to love for the win in his first Davis Cup rubber.
''It's amazing, the crowd behind you. It makes you do stuff that you usually don't do and play better,'' said Bemelmans, who has playing Davis Cup for seven years. ''With the team in the semifinals, this is a highlight for me. This is a tie to remember.''
Canada wasn't expected to fare well after arriving without injured top-30 players Milos Raonic and Vasek Pospisil.
Argentina will travel to Belgium in three months after putting away Serbia 3-0 thanks to first-time Davis Cup pair Carlos Berlocq and Leonardo Mayer sweeping aside Nenad Zimonjic and Viktor Troicki 6-2, 6-4, 6-1.
Troicki, who lost his singles on Friday from two sets up, was a gamble that didn't pay off, as he was listless in a pairing that didn't even earn a break point chance on the indoor clay in Buenos Aires.
Novak Djokovic wasn't available for Serbia after winning Wimbledon last weekend.
Argentina, a four-time runner-up, last met Belgium, the runner-up in 1904, in 1948.
On the grass at Queen's Club in London, brothers Andy and Jamie Murray defeated Jo-Wilfried Tsonga and Nicolas Mahut 4-6, 6-3, 7-6 (5), 6-1 for Britain to lead France 2-1.
''We played an unbelievably high-level match against a top team,'' Andy Murray said. ''It was an absolutely fantastic atmosphere. To play and represent your country with your brother in a match like this is very special.''
The Murrays had not played together since losing in the second round at Indian Wells in 2013.
Third-ranked Murray is set to play 11th-ranked Gilles Simon in the first of the reverse singles on Sunday, giving him an opportunity to put Britain into the semifinals for the first time since 1981. France was runner-up last year.
Murray, who beat Tsonga in singles on Friday, took a tumble on Saturday and hurt his hip, but said he'll be OK for Sunday.
''The trick job now is to go and rest and recover, get patched up, and hopefully put on a good performance, but it will be extremely tough again,'' he said.
Australia avoided defeat in Darwin against Kazakhstan when Lleyton Hewitt and Sam Groth beat Andrey Golubev and Aleksandr Nedovyesov 6-4, 7-6 (4), 6-2.
But the odds remain in Kazakhstan's favor. Australia has come back from 2-0 down only once, in the 1939 final against the United States.
On Sunday, Australia No. 1 Nick Kyrgios opens the reverse singles against Mikhail Kukushkin, and Thanasi Kokkinakis is scheduled to play Nedovyesov.
Kazakhstan, competing in Davis Cup as an independent team since 1995, is attempting to advance to the semifinals for the first time.