Defending champions Croatia, 2018 runners-up France, last year's semi-finalists Spain and the United States, plus wildcards Argentina and Great Britain are already in the finals, with today’s contests taking place to establish who will join them.

In the first contest to finish Australia sealed an unassailable 4-0 lead at the Memorial Drive Tennis Club in Adelaide when John Peers and Jordan Thompson came together to win the doubles rubber before Alexei Popyrin triumphed in the following singles tie.

Peers and Thompson won their match against Mirza Basic and Tomislav Brkic 7-5, 6-1 and Popyrin beat Nerman Fatic 6-1, 7-6.

Those results followed singles wins form Alex de Minaur and John Millman yesterday, meaning Australia are into the Davis Cup Finals in Madrid in November.

Elsewhere, in a much tighter tie Japan squeezed past China 3-2 at the Guangdong Olympic Sports Centre.

After yesterday’s singles the tie was level at 1-1 and China initially went ahead today when Mao-Xin Gong and Ze Zhang won the doubles rubber 5-7, 7-5, 6-4 against Ben Mclachlan and Yasutaka Uchiyama.

With a place in the finals on the line, though, Japan refused to lie down as Yoshihito Nishioka then thrashed Yibing Wu 6-2, 6-0.

Japan sealed the win in the final rubber when Tero Daniel beat Zhe Li 6-3, 6-7, 6-3.

In Germany, the world number three Alexander Zverev helped seal a 5-0 win for his country against Hungary by beating Gábor Borsos in the fourth rubber 6-3, 6-4.

Earlier, Tim Puetz and Jan-Lennard Struff had beaten Borsos and Péter Nagy 6-2, 6-3, while Philip Kohlschreiber won the fifth rubber 6-7, 6-3, 10-5 against David Szintai.

At 3-0 the tie was already over, but the two sides decided to still play the final two rubbers regardless, which Hungary may have then regretted considering the final result. 

Other countries to win their qualifier and advance into the November finals include Serbia, who beat Uzbekistan 3-2 in the absence of world number one Novak Djokovic; Italy, who beat India 3-1 away from home; and Kazakhstan, who saw off visitors Portugal 3-1.

Canada edged past Slovenia away from home 3-2 in part thanks to Denis Shapovalov, who won both his singles rubbers, while a victory for Robin Haase in the crucial fourth rubber between The Netherlands and the Czech Republic saw the Dutch into the finals 3-1. 

Russia beat Switzerland, who were playing without 20-time Grand Slam champion Roger Federer, 3-1 and Chile beat Austria 3-2.

In South America Belgium saw off Brazil 3-1 at the Ginasio Presidente Tancredo Neves in Uberlândia to seal their place in the Finals, while Colombia comfortably dispatched Sweden 4-0 at the Palacio de los Deportes in Bogota.

It means all 18 places at the inaugural Davis Cup Finals have been filled, with the so called “World Cup of Tennis”, set to go ahead from November 18 to 24 in Madrid.