Novak Djokovic was firing on all cylinders as he dismantled home favourite Alex De Minaur to reach the quarter-finals of the Australian Open for the 13th time.

The nine-time champion's damaged left hamstring has dominated discussion around his chances of triumphing again at Melbourne Park but there were no signs of discomfort here as he stormed to a 6-2 6-1 6-2 victory with a ruthless display.

It was a very uncomfortable evening, though, for De Minaur, the last remaining home singles hope, on Rod Laver Arena as he was outplayed in all areas.

Seeded fourth but a clear favourite, the Serbian said: "A week ago I didn't really think about the title, I just thought about being in a good enough condition to play the next match.

"Tonight, the way I played, the way I felt, gives me reason now to believe that I can go all the way."

On his hamstring, Djokovic said: "I didn’t feel anything today. Today was great. I thank my medical team, thank God, anybody that really helped me.

"I don’t want to celebrate too early. I know things can change really quickly and I don’t take anything for granted. I’m really pleased with the way I moved today and the way I hit the ball."

A shell-shocked De Minaur said: "I think what I experienced today was probably Novak very close to his best, I would say. To me, if that’s the level, I think he’s definitely the guy that’s going to take the title."

Fifth seed Andrey Rublev came through a frenetic encounter

Djokovic will now meet Andrey Rublev, who rallied back from the brink to edge Holger Rune and book a second quarter-final at Melbourne Park courtesy of a lucky net cord on match point that sealed a 6-3 3-6 6-3 4-6 7-6 (11-9) cliffhanger.

Fifth seed Rublev had to do it the hard way, having been 5-2 down in the final set at Rod Laver Arena and needing to save two match points to take contest into a 10-point tiebreak of unrelenting tension.

He slipped 5-0 behind in the breaker but roared back to lead 9-7 before ninth seed Rune saved two match points in a late twist.

It took the net cord to separate them, with Rublev's final return clipping the net and popping over on the third match point, leaving the Dane no chance.

Rublev dropped flat on his back behind the baseline before apologising to his young opponent.

"It's not a roller coaster, it’s like they put a gun to your head," said the 25-year-old. "I never in my life was able to win matches like this. It’s something that I will remember for sure all my life. I have no words, I’m shaking.

"Now I can go to the casino. If I (bet), for sure I’m going to win."

It was the cruellest way for Rune to lose, and the ninth seed said: "Of course, it’s not the end of the world, but it hurts.

"It was super close. I had my chances. He played well, as well. The match points, nothing really to do. The luck was on his side. I think I did a lot. I fought until the end."

The other last-eight clash in the bottom half will be an unexpected all-American affair between 25-year-old Tommy Paul and 20-year-old Ben Shelton.

Big-serving Shelton has put together an amazing run at not just his first Australian Open but on the first trip of his life outside the US.

He claimed a second five-set win of the tournament, beating countryman JJ Wolf 6-7 (5) 6-2 6-7 (4) 7-6 (4) 6-2.

Shelton, who is still in college, said: "It’s definitely a surprise. I got on the plane with no expectations. I know that it’s very hard to adjust to Australia from the United States just with the jet lag, time change and everything.

"Never being out of the United States, I knew it would be a struggle. So I think it maybe has helped me a little bit kind of not having that expectation or the feeling that I have to perform, but being able to just go out there, be myself and play free."

Paul, ranked 35, made it three Americans through to the last eight with a 6-2 4-6 6-2 7-5 victory over Andy Murray’s conqueror Roberto Bautista Agut.