Nick Kyrgios has completed an unbeaten group stage for Australia (3-0) at the ATP Cup after defeating world No.6 Stefanos Tsitsipas in a dramatic three-setter.

In a battle of two big servers, the pair went to three tiebreaks, with Kyrgios claiming the first and third ones for a 7-6(7) 6-7(3) 7-6(5) triumph.

With these two entertainers, the match was guaranteed to be entertaining, and it delivered.

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In the third set tiebreak, Kyrgios held match point at 6-5 with Tsitsipas to serve, and a return winner gave the Aussie the victory.

In bizarre scenes during the break between the first and second sets, Tsitsipas smashed his racquet, injuring his dad in the process and causing his mum to come from the stands to tell him off.

It appeared to have little effect with Tsitsipas then receiving a point penalty for unsportsmanlike conduct early in the second set when he smashed a ball into his unfortunate bench, this time just missing his dad.

That was enough for his father, who relocated behind the court-side bench for the rest of the match as Tsitsipas’ mum returned to give her son another spray. “It happened accidentally. I didn’t mean to do it and straight away forgot about it and moved on from there,” Tsitsipas said.

“I wasn’t aiming to do that, so it went out of control, unfortunately.”

All eyes were on Kyrgios to see if he would be on his best behaviour after starting the year with a suspended 16-match ban hanging over his head. But the former world No.13 looked like a choirboy compared to the hot tempered Tsitsipas on Tuesday night.

Not that Kyrgios was judging his Greek opponent.

“I didn’t see it (incident). I don’t think he meant it as well. I don’t think you should be giving it too much attention or looking too far into it, to be honest,” Kyrgios said.

“I’ve done some stupid things as well in the heat of the moment, so it was obviously an accident.”

Asked in his on-court interview weather he was conciously working on his behaviour, Kyrgios responded: “I’m trying, I’m trying”.

It’s a confidence-boosting win for Kyrgios with the Australian Open given Tsitsipas is rated one of the top hopes to challenge men’s tennis’ big 3 for the title at Melbourne Park.

“It was exhausting but a lot of fun. I knew it was going to be very tough... he’s an amazing player and so young and is going to do some special things in this sport,” said Kyrgios, who missed his last match with a sore back.

Nick Kyrgios impressed against Stefanos Tsitsipas. Source: AAP

Australia was already assured of a berth in the playoff stage after clinching Group F by winning ties against Canada and Germany, but was looking to stay perfect.

Around the same time Kyrgios beat Tsitsipas, Australia’s first-up playoff opponent was confirmed - Great Britain, who despite being without Andy Murray was able to win Group C.

Earlier, John Millman had to come from behind to claim a three-set thriller against Greece’s world No.486 Michail Pervolarakis.

The Aussie No.3, playing due to Alex de Minaur’s withdrawal from the final tie of the group stage which is a dead rubber, dropped the opening set to the little-known Greek No.2.

But he then looked dominant on serve in the final two sets and did enough to earn the win in a third-set tiebreak, 4-6 6-1 7-6(1).

Millman was praised for his class during the second set after Pervolarakis slipped and appeared to roll his ankle. Millman immediately went to the other side of the court to help him up.

Australia had already qualified for the playoff stage of the inaugural ATP Cup, with thanks to Alex de Minaur’s victories over Germany’s world No.7 Alexander Zverev and Canada’s No.14 Denis Shapovalov in group play to help the Aussies qualify for the tournament’s final eight.

The action in Brisbane will then be completed with the doubles, with Chris Guccione and John Peers to face Greece’s singles players, Tsitsipas and Pervolarakis.

NADAL FLAWLESS AS ‘BRUTAL’ AUSSIE HEAT NEARLY DERAILS DJOKER

RACQUETS BROKEN, BOTTLES THROWN: FRENCHMAN’S ‘PATHETIC’ MELTDOWN

Earlier, Alexander Zverev had another rough outing as Denis Shapovalov completed a dominant victory to put Canada level with Germany at the ATP Cup.

After suffering a meltdown in a singles loss to Greece’s Stefanos Tsitsipas, due to horror serving woes, Zverev had even more struggles in what turned out to be an easy match for Shapovalov, who won 6-2, 6-2 to tie the matchup 1-1.

Zverev had difficulty with his serving to start Tuesday’s (AEDT) match, and they didn’t get any better from there.

The most strange thing about Zverev’s form is that he looked actually quite good for one set and a half vs De Minaur. Was set and break up and then disappeared. These last two matches have been... scary bad. — José Morgado (@josemorgado) January 7, 2020

Oh my lord. Zverev almost hit the baseline with that second serve. Back to back double faults to get broken and Shapovalov leads 6-2, *3-0. Won the last 6 games, so a moral bagel. — José Morgado (@josemorgado) January 7, 2020

Zverev had seven double faults in the match, and won just 68 percent of the points in which his first serve went in.

The serving woes clearly affected Zverev, who became visibly frustrated as the match came to an end, before ultimately suffering the loss.

Shapovalov d Zverev 6-2, 6-2. Not that close. Sasha’s head unfortunately is in a bad place at the moment. Happens to all of us. He will get through this. Choose to support him rather than rip him. Patience... 🇩🇪❤️🖤 pic.twitter.com/He7tAG7n21 — Craig O'Shannessy (@BrainGameTennis) January 7, 2020

With Canada and Germany tied at 1-1, it came down to the doubles match to decide the victor. Kevin Krawietz and Andreas Mies fell to Shapovalov and Felix Auger Aliassime, giving the Canadians second spot in the group.

PAIRE LOSES IT IN TESTY OPENER

Benoit Paire got the best of Dusan Lajovic in France’s opening match against Serbia, but it wasn’t without some heated emotions.

Paire was forced to overcome both his opponent and his emotions in his 6-2, 6-7 (6/8), 6-4 win.

Paire won the first set comfortably and broke Lajovic to serve for the set at 5-4.

But the Serbian broke back and then took the tiebreak against an increasingly angry Paire, who promptly smashed his racket and then threw two water bottles onto the court at the change of ends.

French captain Gilles Simon tried to calm him down but it took a courtside visit from Monfils to ease the tensions and Paire regrouped to take the third set and the match.

“Honestly, you know, if I’m alone on court I can break more than the racket, I can destroy all my rackets and leave the court,” he said.

“So that’s why they told me, just stay relaxed and you will see what happens.”

Ultimately, though, Djokovic rallied Serbia to an impressive victory in the singles and doubles, securing a spot in the quarterfinals.

AUSTRALIA [3-0] def Greece [0-3]

No.2 singles: John Millman (AUS) def Michail Pervolarakis (GRE), 4-6 6-1 7-6(1)

No.1 singles: Nick Kyrgios (AUS) def Stefanos Tsitsipas (GRE), 7-6(7) 6-7(3) 7-6(5)

Doubles: Michail Pervolarakis and Stefanos Tsitsipas (GRE) v Chris Guccione and John Peers (AUS)

OTHER MATCHES

BRISBANE (Group F)

Canada [2-1] def Germany [1-2], 2-1

No.2 singles: Jan-Lennard Struff (GER) def Felix Auger-Aliassime (CAN), 6-1 6-4

No.1 singles: Denis Shapovalov (CAN) def Alexander Zverev (GER), 6-2 6-2

Doubles: Felix Auger-Aliassime and Denis Shapovalov (CAN) def Kevin Krawietz and Andreas Mies (GER), 6-3 7-6(4)

Australia wins Group F

SYDNEY (Group C)

Great Britain [2-1] def Moldova [0-3], 3-0

No.2 singles: Cam Norrie (GBR) def Alexander Cozbinov (MOL), 6-2 6-2

No.1 singles: Dan Evans (GBR) def Radu Albot (MOL), 6-2 6-2

Doubles: Jamie Murray and Joe Salisbury (GBR) def Radu Albot and Alexander Cozbinov (MOL), 6-2 6-3

Belgium [2-1] def Bulgaria [2-0], 2-1

No.2 singles: Dimitar Kuzmanov (BUL) def Steve Darcis (BEL), 6-0 6-3

No.1 singles: David Goffin (BEL) def Grigor Dimitrov (BUL), 4-6 6-2 6-2

Doubles: Sander Gille and Joran Vliegen (BEL) def Grigor Dimitrov and Dimitar Kuzmanov (BUL), 3-6 6-4 [10-7]

Great Britain wins Group C

PERTH (Group D)

Russia [3-0] def Norway [1-2], 3-0

No.2 singles: Karen Khachanov (RUS) def Viktor Durasovic (NOR), 6-2 6-1

No.1 singles: Daniil Medvedev (RUS) def Casper Ruud (NOR), 6-3 7-6(6)

Doubles: Teymuraz Gabashvili and Konstantin Kravchuk (RUS) def Viktor Durasovic and Casper Ruud (NOR), 7-6(4) 6-4

Italy [2-1] def United States [0-3]

No.2 singles: Stefano Travaglia (ITA) def Taylor Fritz (USA), 7-6(3) 7-6(1)

No.1 singles: Fabio Fognini (ITA) def John Isner (USA), 6-4 7-6(5)

Doubles: Simone Bolelli and Fabio Fognini (ITA) v Austin Krajicek and Rajeev Ram (USA)

Russia wins Group D

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