Defending champion Roger Federer takes aim at an incredible 14th Australian Open quarter-final Monday when he faces one-time training partner Marton Fucsovics, while Novak Djokovic looks to reach his 10th.
The Swiss maestro, 36, has made at least the last eight every year since 2004, bar a hiccup in 2015, with the odds of him doing so again heavily stacked in his favour.
Fucsovics has never beaten anyone ranked higher than 13th and is making his tournament debut.
Their match is an afternoon affair on Rod Laver Arena with Djokovic securing top billing in the evening in what is shaping as a tough test against talented Chung Hyeon.
The glasses-wearing South Korean, ranked 58, upset fourth seed Alexander Zverev in five sets in the round of 16 and Djokovic is wary.
"He's playing great. He's fit. He doesn't have too many holes in his game," he said.
"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."
Chung beat rising Russian Andrey Rublev to claim his first title at the NextGen ATP finals in Milan last year.
Whoever wins will play either Austrian fifth seed Dominic Thiem or American surprise packet Tennys Sandgren for a place in the semi-finals.
Federer, chasing a 20th Grand Slam title and a sixth in Australia, will face off against either Czech Tomas Berdych or Italy's Fabio Fognini if he comes through his match.
Former champion Angelique Kerber is in fine touch as she looks to repeat her 2016 feat, when she beat Serena Williams in the final.
After ousting Maria Sharapova in the last round, she takes on Taiwan's Hsieh Su-wei.
Following a forgettable 2017, the German is enjoying herself on court again which she said was half the battle.
"I'm just trying to go out there, take all the experience I've had, from what I learned, and enjoy it again," she said.
"I'm just enjoying my tennis, fighting for every single ball."
Beating Hsieh will line-up a quarter-final clash with either French eighth seed Caroline Garcia or American 17th seed Madison Keys.
World number one Simona Halep is also in action after her third round epic, where she was pushed to 15-13 in the third set by American Lauren Davis.
How she backs up will be keenly watched, although she has been given until late afternoon for extra recovery before she faces Japan's Naomi Osaka.
The final women's match sees sixth seed Karolina Pliskova take on fellow Czech Barbora Strycova.