Sydney, Australia, 9 January 2020 | AAP

Australia has roared into the ATP Cup semifinals with a rollicking doubles win from shock first-time pairing Alex de Minaur and Nick Kyrgios.

In a daring selection gamble, Australian captain Lleyton Hewitt replaced doubles specialists John Peers and Chris Guccione with his two singles spearheads after an inspired Dan Evans levelled the tie for Great Britain with an epic victory over De Minaur.

But a lion-hearted De Minaur rebounded from his three-hour, 22-minute singles loss to pull off a rousing 3-6 6-3 18-16 triumph with Kyrgios over two-times Grand Slam doubles champion Jamie Murray and Joe Salisbury.

“It was a tough one,” Hewitt said of rolling the dice on the pairing and in particular playing De Minaur after his singles loss.

“He’s (De Minaur) a hell of a doubles player when he actually plays; he doesn’t play that much.

“We threw out a bit of firepower and it ended up paying off – just.”

The thrilling triumph, after saving four match points in the super-tiebreak, almost raised the roof at the new-look Ken Rosewall Arena and fired Australia into a semifinal showdown on Saturday night with Rafael Nadal’s Spanish Davis Cup champions or Canada.

Staring down their fourth match point, De Minaur and Kyrgios each rifled spectacular backhand return winners before Kyrgios closed out the contest with an undeliverable serve.

A jubilant Kyrgios carried De Minaur off court to celebrate with the Australia’s courtside box and related how he played the role of motivator for De Minaur during the match.

“He just needed a bit of guidance that’s all,” Kyrgios said after De Minaur mentioned he was carried by his partner.

“Of course (I’m the calm head). My past record says I am.

“He just gets pretty down on himself and I try to keep him positive.”

Revelling in the team environment, Kyrgios had given Australia a flying start with an emphatic 6-2 6-2 win over Cameron Norrie in Thursday’s opening match before Evans denied De Minaur 7-6(4) 4-6 7-6 (2) in the match of the tournament.

But few could have predicted the drama to follow, with De Minaur and Kyrgios never having paired up before.

Despite their proven singles prowess, neither are doubles newcomers.

De Minaur played 11 doubles tournaments last year.

He partnered Peers to knock off Jack Sock and Leander Paes, both multiple Grand Slam doubles champions, as well as the top-ranked pairing of Robert Farah and Juan Sebastian Cabal to make the semi-finals in Washington.

Kyrgios also contested 11 doubles events in 2019, his most notable win a victory with Sock over Rafael Nadal and Stefanos Tsitsipas.

But Thursday’s win was another level, given the high stakes and massive $22 million prize money on offer at the inaugural ATP Cup.

Russia will face Argentina in Thursday night’s second quarterfinal.

Spain and Belgium clash on Friday night, after the Novak Djokovic-led Serbia take on Canada in that day’s first quarterfinal.