Murray yet to drop a set en route to quarter-finals

Melzer was expected to provide Murray with his first serious test of the tournament, but proved no match for the Scot, who has yet to drop a set in Melbourne as he bids to land his first grand slam title.

Murray produced a mature, controlled performance to win 6-3 6-1 6-1 in one hour and 44 minutes, contrasting sharply with that offered by Melzer, the Austrian spraying the ball all over Rod Laver Arena as his all-or-nothing game was woefully exposed.

Murray, the world number five, will meet Alexandr Dolgopolov in the last eight after the Ukrainian stunned fourth seed Robin Soderling in a five-set thriller.

And the 23-year-old admitted he was surprised by the ease of his win.

"Yeah, he had a good year on tour last year, I was surprised but I played a great match," Murray said.

"I am hitting the ball well right now and have played four good matches so far."

However, Murray accepts it is likely to get tougher against emerging star Dolgopolov.

"I have known him quite a while and played him when we were young in Davis Cup. He is unorthodox but is a tough player," added Murray, who was watched by mum Judy after she missed the clash with Guillermo Garcia-Lopez on Saturday.

"My brother was playing doubles at the same time and I am not the favourite son so I got bumped for that one," Murray joked. "My brother lost that one so she was able to come today."

Murray asserted his authority from the off and quickly established two break points for a 3-1 lead. The first one was saved but the second, set up by a brilliant backhand winner, saw Melzer power a backhand beyond the baseline.

Murray promptly undid all his hard work, however, Melzer hitting straight back when the fifth seed allowed himself to be pushed backwards and the Austrian clinched the game with a drive volley.

Melzer was struggling on serve, though, especially his second which Murray punished with ease to regain the advantage at 4-2.

And despite a scare when serving for the set when Melzer forced a break point, Murray closed it out.

The momentum was with Murray, who was cheered on from the players' box by comedian Billy Connolly, and he struck early in the second set by cracking a forehand cross-court winner to break.

Murray threatened again at 3-1 as Melzer's frustration began to mount.

The left-hander saved one break point but then gifted Murray another with an awful backhand into the net, prompting him to slam his racket onto the court.

Murray too had cause for complaint when he appeared to clinch the break with a clean winner off a ball which was called narrowly out.

Melzer appealed and the ball was found to have caught the line, meaning the point was replayed. And when Melzer won it, Murray sarcastically offered a thumbs-up to the line judge.

It mattered little as Murray claimed the break anyway after using his irritation to good effect.

A comfortable hold and a break to 15 then saw the 23-year-old from Dunblane move two sets up.

Melzer suggested he might be getting his act together at the start of the third as some fine hitting from the back of the court set up two break points.

But Murray wriggled back to deuce before sending down two big aces to complete the escape.

And the writing was on the wall for Melzer when some more wayward hitting enabled Murray to break for a 3-1 lead shortly after.

That quickly became 5-1 as a routine hold was followed by another break thanks to a stunning pass as Melzer approached the net.

The Scot had little problem in serving it out as he cruised home to maintain his record of having not dropped more than three games in a set in the tournament.