'Take a bow': Qualifier's stunning 32-year Australian Open first

Unheralded qualifier Aslan Karatsev is the first man into the Australian Open quarter-finals, continuing an extraordinary dream run in his first grand slam.

Two days after seeing off eighth seed Diego Schwartzman, Karatsev fought back from two sets down to outlast 20th-seeded Canadian Felix Auger-Aliassime 3-6 1-6 6-3 6-3 6-4.

'BEYOND TENNIS': Nick Kyrgios' latest mockery of Novak Djokovic

'CAN'T BELIEVE IT': Tennis world stunned by 'insane' Naomi Osaka drama

"It was really tough in the beginning to play with him," Karatsev said.

"He's a really good player, he's really fast and it took me two sets to find how to play."

Karatsev will face either third seed Dominic Thiem or 18th seed Grigor Dimitrov in the quarter-finals.

"I'll be ready for everyone," he said.

After being broken at 5-1 to hand Auger-Aliassime the second set, Karatsev wouldn't lose another service game for the rest of the match.

The Russian flipped the momentum at 2-2 in the third set when he broke Auger-Aliassime's serve and kicked on from there.

Karatsev broke Auger-Aliassime in the Canadian's second service game of the deciding set and never really looked back.

When serving out the contest at 5-4, Karatsev quickly earned three match points - but only needed the first one, dispatching a cool forehand winner to claim a brilliant comeback win.

Karatsev's achievement marked the first time in 32 years that a qualifier had advanced to the quarter finals at the Australian Open - the last man to achieve the feat was Croatia’s Goran Ivanisevic in 1989.

The records didn't stop there for Karatsev - he also became the first male player to make the quarter finals in their debut grand slam since Alex Radulescu at Wimbledon in 1996.

The little-known Russian also became the lowest ranked player to advance to the Australian Open quarter finals since Patrick McEnroe, the younger brother of John, in 1991.

Medvedev overcomes Australian Open meltdown to advance

Doing his idol John McEnroe proud, Daniil Medvedev delivered a spectacular multi-lingual outburst to keep his Australian Open title hopes alive at Melbourne Park.

The world No.4 extended his winning streak to 17 matches with a watershed 6-3 6-3 4-6 3-6 6-0 victory over Serbian Filip Krajinovic on Saturday.

But not before his coach stormed out of Rod Laver Arena mid-match after copping stunning verbal sprays from Medvedev in Russian, French and English.

"He said just before leaving that he was sure that I was going to win the match but that he's going to leave me alone to be more calm," Medvedev said.

"So I won't tell more because that was a good thing to do and luckily I won."

The 25-year-old's performance certainly impressed McEnroe, tennis's original super-brat saying in commentary that Medvedev was his favourite player on tour to watch.

"When John says some good things about me it just makes me happy," Medvedev said.

"He's an idol for many kids. He's a legend of our sport and what else can I say when someone like him says something good about you?

"It means you are doing things right."

Incredibly, it was Medvedev's first-ever five-set victory, having lost his previous six matches that have gone the distance - including the 2019 US Open final to Rafael Nadal.

With Yahoo Sport Australia/Chris Young

Click here to sign up to our newsletter for all the latest and breaking stories from Australia and around the world.