US Open quarter finalist Alex de Minaur gave the Australians an unassailable 2-0 lead against Belgium in Hamburg in the first Group C clash.

The 23-year-old saved both break points he faced to move past David Goffin 6-2, 6-2 after 67 minutes.

De Minaur has now beaten the Belgian in all three matches they have played.

In the first match of the tie, Jason Kubler defeated Zizou Bergs 6-4, 1-6, 6-4.

The 29-year-old won 64 per cent of his second serve points and twice rallied from a break down in the third set to triumph after two hours and nine minutes.

Matthew Ebden and Max Purcell then downed Sander Gille and Joran Vliegen 6-1, 6-3 to secure a 3-0 victory for Australia.

Elsewhere in Bologna, Sweden's Elias Ymer got his country off to start against Argentina in Group A as he got the better of Sebastian Baez 6-4, 3-6, 7-6 in the opener.

The 26-year-old had squandered two match points in the third set but eventually managed to hold on for the tiebreak win.

His younger brother Mikael then shocked world number 17 Diego Schwartzman 6-2, 6-2 to seal the win.

The Argentines then took a consolation point in the final meeting as Maximo Gonzalez and Horacio Zeballos beat Andre Goransson and Elias Ymer 3-6, 6-3, 6-2.

Dutchman Tallon Griekspoor fended off a Kazakh comeback from Mikhail Kukushkin to win 6-1, 3-6, 6-3 in Glasgow.

His compatriot Botic van de Zandschulp followed it up with a comeback win of his own, beating Alexander Bublik 3-6, 6-1, 6-4 in the Group D match-up.

Kazakhstan then managed to get a consolation point courtesy of Bublik and Aleksandr Nedovyesov who dispatched Wesley Koolhof and Matwe Middelkoop 6-4, 1-6, 6-3.

Canada snuck past South Korea 2-1 overall to top the standings in Group B in Valencia.

Vasek Pospisil got the Canadians off to a winning start as he beat Hong Seong-chan 4-6, 6-1, 7-6 but Kwon Soon-woo levelled the score with a remarkable 7-6, 6-3 victory against 2021 US Open semi-finalist Félix Auger-Aliassime.

Auger-Aliassime as he excelled in the deciding doubles match with Pospisil against Nam Il-sung and Song Min-kyu, winning 7-5, 5-7, 6-3.