Novak Djokovic finding his rhythm after long injury lay-off and ahead of fourth round clash with Hyeon Chung

NOVAK Djokovic’s fitness and form was one of the big question marks heading into the Australian Open and the Serb has passed with flying colours but is he about to face his biggest test yet against the man that stunned No.4 seed Alexander Zverev?

Novak Djokovic has breezed through to the fourth round.

IT was the great unknown.

How would six-time Australian Open champion Novak Djokovic return from the troublesome elbow injury, which stalled his 2017 season after Wimbledon.

If the first three matches are any indication, then the former world No.1 has shown — somewhat incredibly — that lightening could strike twice at Melbourne Park.

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Less than 12 months after Roger Federer and Rafael Nadal wound back the clock in Melbourne, it is Djokovic’s turn to defy the doubters.

The Serb has sailed into the round of 16, winning 40 of a possible 44 service games going into a tricky assignment against South Korean sensation Hyeon Chung, who stunned world No.4 Alexander Zverev in five sets on Saturday.

Novak Djokovic has breezed through to the fourth round.

Djokovic, who uses meditation as part of meticulous preparation, will want to be well-rested on Monday against bespectacled Chung, just the third South Korean ever to reach the second week of a grand slam.

Chung has all the tools, and, more importantly, the tank, to trouble an underdone Djokovic.

The Serb has feasted on short rallies this campaign, but appeared vulnerable when forced into nine-plus-shot exchanges (51-39).

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Djokovic has spent a tick under seven hours on the court despite winning comfortably — every minute counts at the pointy end of the slam.

“It was great for me to actually get into that long exchanges and rallies, to get some rhythm,” Djokovic said after wiping the floor with Albert Ramos-Vinolas.

“I’m really pleased with where my game is at the moment.

Hyeon Chung of Korea celebrates after defeating No.4 seed Alexander Zverev. Picture: Getty

“I know that matches from this moment onwards will get tougher and tougher.

“I’m not first time in this particular situation.

“I’m looking forward to the next challenge.

“(Chung) is playing great. He’s fit. He doesn’t have too many holes in his game … you can see he’s a hard worker. It pays off.

“Into second week, it’s going to be a game of small margins. So let’s see what happens.”

If games were to go on rankings, Djokovic, who meditates daily, must go through fifth-seed Dominic Thiem to book a potential semi-final date with reigning Australian Open champion Roger Federer.

THE MATCH-UP: DJOKOVIC V CHUNG

NOVAK DJOKOVIC (Serb)		HYEON CHUNG (Kor)
14	RANKING	58
30	AGE	21
187cm	HEIGHT	187cm
77kg	WEIGHT	87kg
12	GRAND SLAM TITLES	0
$109,805,403	PRIZEMONEY	$1,687,063
Right-handed	PLAYS	Right-handed