ATP Cup starts off with gaffe ...

Organisers played a wrong national anthem for Moldova ahead of their tie against Belgium in Sydney.

Denis Shapovalov won the battle of the next generation against Greek Stefanos Tsitsipas to help Canada to an emphatic 3-0 victory in the inaugural ATP Cup men's team event in Brisbane on Friday.

Shapovalov, the baby-faced 20-year-old left-hander, gave Canada an unassailable 2-0 lead in the tie with a 7-6(6), 7-6(4) win over world number six Tsitsipas at the Patrick Rafter Arena.

The $15 million ATP Cup, which features 24 nations competing in Perth, Brisbane and Sydney over 10 days, is a solid platform for the world's top players to prepare for this month's Australian Open.

German Alexander Zverev started brightly by going two breaks up against Australian number one Alex de Minaur in the opening set but suffered a spectacular meltdown to lose 4-6, 7-6(3), 6-2 as Australia sealed the tie.

As the match progressed, De Minaur, 20, used his attritional tennis and never-say-die attitude to frustrate Zverev, who smashed his racket seven times in the second set in front of a partisan crowd.

A serving masterclass from an emotional Nick Kyrgios had given the hosts the lead after the right-hander comfortably beat Jan-Lennard Struff 6-4, 7-6(4).

The mercurial Kyrgios has pledged a A$200 ($140) donation for every ace he serves during Australia's summer of tennis in support of relief and recovery efforts for victims of the country's bushfire catastrophe and he contributed handsomely to the cause by smashing 20 of them against his German opponent.

His home town of Canberra has been severely affected by the bushfires and a number of Australian sports stars have rallied behind Kyrgios, who has received lot of praise on social media.

"I don't really care about the praise too much. We've got the ability and the platform to do something. My home town is Canberra and we've got the most toxic air in the world at the moment, that's pretty sad. It's tough. Sorry," he said, before breaking into tears during a courtside interview.

The participating teams for the ATP Cup were determined by the singles ranking of their best player. Six of the top seven players in the world, barring Swiss great Roger Federer, have arrived in Australia.

The 21-year-old Tsitsipas was considered the favourite going into his match against Shapovalov having defeated Federer and Dominic Thiem to win the ATP Finals in November.

But Shapovalov, who played brilliantly to lead Canada to their first Davis Cup final in November where they lost to Rafa Nadal's Spain, was the better player on the big points.

After more than two hours of power hitting from two of the ATP's most exciting young players in a match featuring no breaks of serve, Shapovalov converted his first match point when Tsitsipas double-faulted on his serve.

The event did not get off to the best start with organisers playing the wrong national anthem for Moldova ahead of their tie against Belgium in Sydney and apologising personally to the team for the blunder. Moldova lost the tie 3-0.

In the day's other tie, Casper Ruud defeated American John Isner to spark an unlikely 2-1 comeback win for Norway.