-Murray not troubled by ankle strain

-To meet Zverev in fourth round

With Novak Djokovic's reign broken, Andy Murray boosted his claim to the Melbourne Park throne with a comprehensive 6-4 6-2 6-4 win over American Sam Querrey to reach the fourth round of the Australian Open on Friday.

Top seed Murray, beaten in four of his five finals in Melbourne by Djokovic, has become raging favourite after the Serb's stunning second round exit on Thursday and the Briton lived up to the billing by trouncing Querrey in a tick under two hours at the Hisense Arena.

Murray was among the many surprised by Djokovic's elimination but was neither dancing on the Serb's grave nor talking up his own hopes of a maiden title in Melbourne.

"It doesn't change anything unless I was to potentially reach the final, because I can't play Novak in the fourth round or in the third round," Murray told reporters after setting up a clash with unseeded German Mischa Zverev.

"I don't worry about that, really. Obviously, if you're to get to the final, then it has an effect. A lot of the times when I've been in the final here, I've played against him. Had some tough ones."

Djokovic's departure aside, Murray appeared free of another bugbear, showing no discomfort on the right ankle he twisted in his previous win against Russian teenager Andrey Rublev.

Although he cruised through the first two sets, the ankle was given a good work-out in the third by the desperate Querrey who dumped Djokovic out of Wimbledon at the same stage last year.

Querrey relied on his huge serve to get him out of myriad jams against Djokovic in that upset but his main weapon misfired for much of the Murray match on a cool, breezy afternoon.

More renowned for his outstanding returning game, Murray finished with eight aces to Querrey's five and broke him five times.

The Scot had a pre-game chat with 11-times grand slam champion Rod Laver and placed a number of sumptuous lobs over the rangy American that would have impressed the Australian great.

One of them captured the break at 4-4 in the opening stanza, a marathon game of 14 points, and Murray rode the momentum to a two-set lead in just over an hour.

The last of 14 Americans in the men's draw, Querrey slipped on a fresh shirt for the third set and the wardrobe change seemed to help.

He rallied from 2-0 down, winning three straight games and breaking Murray for the first time to leave the Scot barking his frustration.

But Murray captured the decisive break in the ninth game with two points that showcased his speed and appetite for gut-busting running.

Flung back and forth across the court by Querrey, Murray chased down ball after ball and the flustered American netted the simplest of volleys to give up break point.

Murray then smacked a passing shot to take his serve and after blowing a first match point with a double-fault, he made no mistake with a huge serve on the second.

"I thought I moved much better today than I did in the first two matches, which is really positive for me," said Murray.

"Each match I think I've improved a little bit. That's a good sign. Hopefully I keep getting better."