SYDNEY (Reuters) - Greece's Stefanos Tsitsipas was clinical as he picked up his first win of the season at the ATP Cup in Brisbane on Sunday against German Alexander Zverev, who was almost reduced to tears due to problems over his serve.
Nick Kyrgios' late withdrawal due to a back problem did not stop Australia from defeating Canada, as the hosts became the first to seal a quarter-final spot with their second 3-0 win in the inaugural team event.
Australia had beaten Germany in their opening tie and qualified for the last eight in Sydney as Group F winners after Germany beat Greece 2-1 in the evening session.
ATP Finals champion Tsitsipas made it five straight wins against the German world No. 7 with a breezy 6-1, 6-4 victory as Zverev cut a frustrated figure with 10 double faults and a first serve percentage of just 45.
Tsitsipas returned to the Pat Rafter Arena for the deciding doubles but went down 3-6, 6-3, 17-15 as Greece suffered their second loss in the inaugural US$15 million (S$20.24 million) ATP Cup, which features 24 nations competing in Perth, Brisbane and Sydney over 10 days.
With just two weeks left until the start of the Australian Open, Zverev needs to find a quick cure for his service woes as he also had 14 double faults in a three-set loss to Australia's Alex de Minaur on Friday.
Zverev smashed his racket repeatedly when playing against de Minaur and against world No. 6 Tsitsipas he flung his racket away twice and appeared almost to start crying as he hid his face in his palms after a service break in the second set.
Tsitsipas, who lost his opening ATP Cup match against Canadian Denis Shapovalov, maintained Zen-like focus in the face of all the drama across the court and closed out the match under 75 minutes.
"Proud of myself, worked very hard for this win. Found solutions, found my rhythm, my pace, knew what I was doing on court," the 21-year-old said in a courtside interview.
Earlier, the mercurial Kyrgios pulled out from the opening singles in Brisbane as a precaution because of a bad back, paving the way for home town favourite John Millman to take down Canada's Felix Auger-Aliassime 6-4, 6-2.
De Minaur then rallied from a set and a break down against fellow 20-year-old Shapovalov to triumph in the battle of next generation stars to seal the tie for Australia.
From 4-2 down in the second set, de Minaur won six straight games to lead 2-0 and ultimately won 6-7 (6-8), 6-4, 6-2 against the Canadian.
Grigor Dimitrov also led Bulgaria to their second win of the event against Moldova as did Russia's Daniil Medvedev, who had an easy 6-3, 6-1 outing against big-serving American John Isner.