Novak Djokovic lost his temper but refused to let the prospect of Australian Open glory slip away as he edged out Alexander Zverev to reach the semi-finals.

The world number one destroyed a racket when trailing 3-1 in the third set, after he and Zverev split the opening two sets, and it was one of a number of moments when the Serbian showed heightened volatility during a 6-7 (6-8) 6-2 6-4 7-6 (8-6) win.

Still bothered by an abdominal problem that he sustained in the third round, Djokovic nevertheless strides on and will face Russian qualifier Aslan Karatsev for a place in the final.

Zverev, who played in a bright yellow headband and vest top, with a gold medallion hanging from his neck, will look back on an opportunity missed.

As well as that third-set lead, Zverev was also up a break at the start of the fourth, but the US Open runner-up lacked the composure to convert those hard-earned positions.

If Djokovic's racket-smashing was a tactical move designed to gee himself up and distract Zverev, then it worked a treat.

A nip-and-tuck opener had gone the way of German world number seven Zverev, who then made a wretched start to the second set and was 4-0 behind in the blink of an eye.

Just as momentum began to swing back Zverev's way in the third, Djokovic went into his rage, with a ball girl summoned to clear up the mess the 33-year-old created.

Back came Djokovic as double faults began to leak from Zverev's racket, and soon they were into a fourth set.

Zverev led 3-0 but Djokovic was not going away, seizing on mistakes from an opponent who by the end of the second tie-break of the match could only wonder what might have been.

An ace from Djokovic finished off the contest. After eight titles at Melbourne Park, a hunger for more continues to define his every performance in Australia.

"Emotionally I feel a little bit drained. We pushed each other to the limit," Djokovic said in his on-court interview.

"Other than in the second set I started pretty poorly in all the other three sets. I lost my service very early in the first, third and fourth and allowed him to swing through the ball a bit more, but I regained my focus.

"I broke that racket and things started to shift a little bit for me in a positive direction."

Novak Djokovic admitted there was plenty of room for improvement after coming through a "difficult spot" at the Australian Open, where Nick Kyrgios thrilled the crowd with an impressive comeback.

Top seed Djokovic was made to work for his 6-3 6-7 (7-3) 7-6 (7-2) 6-3 triumph against Frances Tiafoe as he reached the third round in Melbourne. 

Kyrgios is also through, albeit he even surprised himself by rallying from the brink of defeat to knock out 29th seed Ugo Humbert in the evening session. 

Stan Wawrinka was on the wrong of an upset on Wednesday, but there were no such problems for fellow seeds Dominic Thiem, Alexander Zverev, Diego Schwartzman and Milos Raonic. 

Meanwhile, Denis Shapovalov and Felix Auger-Aliassime will have to put their friendship to one side when they face each other next, the former setting up the all-Canadian clash by beating Bernard Tomic in three sets.

'PASSIVE' DJOKOVIC STILL MAKING PROGRESS

In the first meeting between the pair, the impressive Tiafoe went toe-to-toe with Djokovic on Rod Laver Arena.  

The 23-year-old American's performance – coupled with the Melbourne heat – made the eight-time Australian Open champion sweat, albeit Djokovic felt he could have made life easier for himself.

"I was at times not feeling my timing as well as I normally am. Credit to him. I think he has managed to come out with a great performance and quality of tennis. He put me in a difficult spot," he said. 

"I had my chances early in the second set. If I broke him there, maybe the course of the match would be different.   

"But again, he was holding his serve very well. I was not really using my break-point chances very well. At times I was too passive. Just wasn't feeling the ball today as well as I normally do." 

Next up for Djokovic is another player from the United States in the form of Taylor Fritz, who ousted compatriot Reilly Opelka in a five-set battle.

IN THE NICK OF TIME

Kyrgios described his clash with Humbert as "one of the craziest matches I've ever played" after prevailing 5-7 6-4 3-6 7-6 (7-2) 6-4 - much to the delight of an enthralled audience who watched the drama unfold on John Cain Arena.

The Australian smashed a racket, lost his cool with umpire Marijana Veljovic over a faulty net cord sensor and had to save a pair of match points before eventually coming out on top in a see-saw battle.

"I just remember, down that end, when I was a couple of match points down, I don't know what was going on," Kyrgios - who dropped to his knees after sealing victory - said in his on-court interview.

"If you were inside my head, there were some dark thoughts in there. But I live to fight another day and hopefully I can continue to play good tennis in front of you guys."

His reward is a clash with Thiem, the third seed having dismissed the challenge of German Dominik Koepfer in straight sets as he dropped just six games.

STAN-D AND DELIVER

Wawrinka appeared on course to survive a serious scare when he rallied from two sets down against Marton Fucsovics, but the Swiss was unable to seize on the chances that came his way in a tense tie-break. 

Fucsovics had needed over four hours to overcome wild card Marc Polmans in the previous round and, once again, found a way to get over the finishing line at the end of a Melbourne marathon. 

The Hungarian trailed 6-1 during the decisive breaker, yet hit back to stun the 17th seed 7-5 6-1 4-6 2-6 7-6 (11-9). For Wawrinka, there was frustration at the missed opportunities, albeit he also praised his conqueror. 
  
"From 6-1 up, I started to hesitate a little bit in the way I was playing," he said. "I wanted to put the ball maybe too much in and I [was] not going completely for my shots and that's when I started to miss a little bit and it helped him to come back in the match.  

"He was fighting well, he's a tough player, he's a good player and he deserved to win." 

Daniil Medvedev won a marathon match against Alexander Zverev to send Russia into the final of the ATP Cup for the first time.

The world number four and reigning ATP Finals champion triumphed 3-6 6-3 7-5 at Melbourne Park in a match lasting just under two hours and 40 minutes.

That result clinched victory over Germany in the semi-final after Andrey Rublev had earler fought back in style from a set down to defeat Jan-Lennard Struff 3-6 6-1 6-2.

"We're really happy to get the win, that's the most important [thing," Medvedev said. "Tough matches [for] both of us. Both [Andrey and I] lost the first set. [It was] not easy, because we had two days off before the match. But happy we're in the final. That's the most important."

Zverev appeared in control after breaking to go 3-2 ahead in the second set after winning the first, but Medvedev reeled off four games in a row as the world number seven began to struggle with a lower back problem.

"When it's against Sascha and you are 6-3, 3-2, break down, many times you're going to lose a match," Medvedev said. "But I needed to keep my chances alive for the team first of all, for the country. I just tried to stay there, got a bit tight maybe. I just did my job and I'm really happy about it."

Russia will meet Italy in the final following their defeat of Spain, which was secured by Matteo Berrettini's straight-sets win over Roberto Bautista Agut.

After Fabio Fognini saw off Pablo Carreno Busta in three sets, Berrettini - who has beaten three of the top 13 players in the world without dropping a set in this tournament - won 6-3 7-5 to set up Sunday's Russia showdown.

"It's an unbelievable feeling," said a delighted Berrettini, who was absent last year as Italy failed to progress from their group in the inaugural staging of the event. "Last year I couldn't make it, so I'm really happy that the first time that I played we are into the final.

"I'm feeling good. I'm feeling pumped. I'm feeling great to play not just for me, but for my team and for Italy in general. That's what matters the most. I'm really looking forward to playing tomorrow."

SINNER TO FACE FAMILIAR FOE

There will be an all-Italian affair in the final of the Great Ocean Road Open, with Jannik Sinner to face Stefano Travaglia.

In-form Sinner clinched an impressive 7-6 (7-4) 4-6 7-6 (7-4) win over second seed Karen Khachanov, in a three-hour battle, after his compatriot beat Thiago Monteiro 6-3 6-4.

At the Murray River Open, Felix Auger-Aliassime will meet Dan Evans in the final as each look to secure a first ATP Tour title.

Auger-Aliassime needed only 61 minutes to beat Corentin Moutet, while eighth seed Evans required a minute less to ease past Jeremy Chardy.

Novak Djokovic said it was "a tough one" to take after Serbia's hopes of retaining the ATP Cup title were ended by defeat to Germany.

The world number one scored a tense 6-7 (3-7) 6-2 7-5 victory over Alexander Zverev in their singles rubber, levelling the match after Jan-Lennard Struff beat Dusan Lajovic in three sets.

Zverev and Struff then teamed up in doubles to net a 7-6 (7-4) 5-7 10-7 win over Djokovic and Nikola Cacic.

The singles workout and win sets up the eight-time Australian Open champion well for the start of that grand slam next week, which was the consolation Djokovic could take from defeat.

Speaking about his singles clash with Zverev, Djokovic said: "It was anybody's game really. He was a set up, a couple points here and there in the beginning of the second. I just returned well when I needed to and closed out the match.

"It's never easy playing against Sascha [Zverev] when he's in form, and he's in really good form. We pushed each other to the very limit, and I'm glad that I had such a battle with him.

"It's unfortunate we lost the tie. That's what this competition is all about. It's about the team, not about winning one match, a singles match. Yeah, it's a tough one."

Germany advance to face Russia in the semi-finals on Saturday, with Daniil Medvedev and Andrey Rublev a formidable combination awaiting them.

Spain secured a shot at Italy in the second semi-final, despite a 2-1 defeat to Greece on Friday.

The Spanish team needed just one win in the group-stage match to advance, and that predictably came as Pablo Carreno Busta, ranked 16th by the ATP, beat world number 462 Michail Pervolarakis.

His 6-3 6-4 success could not be matched by team-mate Roberto Bautista Agut, who fell to a 7-5 7-5 defeat against Stefanos Tsitsipas, while Spain retired from the doubles rubber after one game, giving Greece a 2-1 success in the tie.

It remains to be seen whether Rafael Nadal will be fit to play any part in the semi-final, with the 20-time grand slam champion having been absent so far in the campaign due to a back injury.

"He's working very hard to recover his best feelings," said Spain captain Pepe Vendrell.

"Obviously he couldn't play any matches during the week. It's a situation that we have to study. But day by day he's improving. We will see [on Saturday] if he can play."

AWAY FROM THE ATP CUP, WAWRINKA ABANDONS

In the Murray River Open, Stan Wawrinka withdrew from his quarter-final with Jeremy Chardy after beating Australian Alex Bolt in a tough three-set match earlier in the day. Corentin Moutet, Dan Evans and Felix Auger-Aliassime joined Chardy in the last-four line-up.

Evans defeated Borna Coric, who had eliminated Australian hope Nick Kyrgios in his previous match.

All ATP and WTA tournaments are being played at Melbourne Park this week.

Thursday's play was cancelled due to a COVID-19 case affecting a worker from a hotel that accommodated quarantining players, and that meant Friday's schedule was packed.

The Great Ocean Road Open also saw players needing to win two matches in a day to reach the semi-finals, with Karen Khachanov, Thiago Monteiro and the Italian pair of Jannik Sinner and Stefano Travaglia coming through.

Australian Open champion Novak Djokovic could face Dominic Thiem in a mouth-watering semi-final after being handed a tough path to success at Melbourne Park, where Serena Williams will continue her quest for a 24th grand slam singles title.

The Australian Open draw took place on Friday, with world number one Djokovic set to play Frenchman Jeremy Chardy in the opening round of the year's first major tournament.

Amid coronavirus concerns in Melbourne, where Swiss great Roger Federer is absent, Djokovic has set his sights on a ninth crown and 18th major success, but the top seed's title defence is far from straightforward.

Djokovic could face Gael Monfils (fourth round) and sixth seed Alexander Zverev (quarter-final) en route to a possible semi-final against US Open champion and third seed Thiem.

The Serb overcame Thiem in a five-set thriller in last year's Australian Open final, before the latter broke through for his maiden major trophy at Flushing Meadows.

Djokovic could then meet second seed and 20-time major champion Rafael Nadal in a blockbuster final – he blitzed the Spanish superstar in the 2019 Australian Open decider but lost in three one-sided sets in their previous meeting in the French Open final.

Nadal will go head-to-head with another Serb in the first round – Laslo Djere – while Stefanos Tsitsipas could await in the quarters, with 2019 US Open final opponent Daniil Medvedev also on the same side of the draw.

Meanwhile, Williams' bid for a record-equalling 24th slam will begin against German Laura Siegemund.

The 39-year-old Williams has been stuck on 23 majors since winning the Australian Open in 2017 – losing finals at Wimbledon (2018 and 2019) and the US Open (2018 and 2019).

World number one and local hope Ashleigh Barty will meet Montenegro's Danka Kovinic in round one and defending champion Sofia Kenin faces Australian wildcard Maddison Inglis.

The last 16 could see Williams clash with Aryna Sabalenka, Barty meet Petra Martic, Kenin tackle Johanna Konta and three-time major champion Naomi Osaka do battle with last year's runner-up Garbine Muguruza.

Daniil Medvedev and Andrey Rublev produced ruthless performances as Russia cruised into the ATP Cup semi-finals.

Russia followed up their day-one win over Argentina with victory against Japan to ensure they will finish top of Group D.

Rublev got things rolling with an emphatic 6-1 6-3 win over Yoshihito Nishioka and Medvedev dispatched Kei Nishikori in a 6-2 6-4 triumph.

Those results meant the subsequent doubles match – which Japan won – would not be relevant.

"I am really happy for the team," said ATP Finals champion Medvedev, who has now won 12 matches in a row on the tour.

"Reaching the semi-finals is a big step – I am really happy that we made it in both singles. Both matches were straight sets, so really happy for the team and hopefully we can go further than that."

Italy, who had beaten Austria on the opening day, are also through after Fabio Fognini and Matteo Berrettini earned wins in straight sets over France duo Benoit Paire and Gael Monfils on Wednesday.

France play Austria next but neither team can catch Italy in Group C.

Alexander Zverev won a thriller against Denis Shapovalov 6-7 (5-7) 6-3 7-6 (7-4) to ensure Germany defeated Canada.

It was a first win at the ATP Cup for US Open runner up Zverev, who had a miserable tournament in 2020.

That sets up a day three contest for Germany against Novak Djokovic and Serbia where the winning team will progress to face Russia.

KYRGIOS AND WAWRINKA THROUGH

Nick Kyrgios – playing his first tournament for a year – made it two wins from two at the Murray River Open, defeating fellow Australian Harry Bourchier 6-2 7-6 (9-7).

First seed Stan Wawrinka survived a scare before prevailing against Mikhail Kukushkin to win 4-6 6-3 6-1 in just under two hours.

Wawrinka will take on Alex Bolt in the last 16, while Kyrgios should be tested against fourth seed Borna Coric.

At the Great Ocean Road Open, top seed David Goffin crashed out as world number 146 Carlos Alcaraz celebrated a shock 6-3 6-3 victory.

Karen Khachanov and Jannik Sinner were among the seeds who progressed, both winning without dropping a set.

Alexander Zverev insists his latest split from a high-profile coach ended on amicable terms after David Ferrer cut ties with the US Open finalist.

Spaniard Ferrer's decision to walk away leaves Zverev yet again, now at the age of 23, looking for a coach with whom he might establish a long-term partnership.

The German ditched former world number one Juan Carlos Ferrero in early 2018, after six months together, claiming the coach had been "very disrespectful" to other members of his team.

He then linked up with Ivan Lendl in August 2018 but that lasted just under a year, with Zverev reportedly criticising the eight-time grand slam winner's focus.

This time, Zverev and former world number three Ferrer have not hinted at any animosity or disagreements.

They teamed up in July 2020, and Zverev said of their break-up: "I would like to thank David for the months we have shared, the times on and off the court, wishing him only the best in the future.

"I also want to thank his family for giving me the chance to spend precious weeks with David during these difficult times. I have tremendous respect for the way David played and coaches tennis."

Ferrer helped Zverev battle through to the US Open final in September, where he led by two sets but was ultimately beaten by Dominic Thiem.

Zverev also won a pair of titles in Cologne in October and reached the final of the Masters 1000 event in Paris.

But they are going their separate ways as the new season begins, with the Australian Open just weeks away.

Ferrer said: "At the end of the year, a decision had to be made, I spoke with Sascha [Zverev] and told him that I preferred not to continue, that we were not going to continue next season. Not for anything special, I just didn't think it was time."

Speaking to tennis website Punto de Break, Ferrer added: "Absolutely nothing has happened between us, everything is still fine, in fact I am very grateful to him for the opportunity he gave me to travel with him during that stretch of the season.

"During those months we had a good coexistence, everything was perfect."