Stefanos Tsitsipas believes it is "insane" that he is preparing for a clash against two-time reigning Australian Open champion Roger Federer as the Greek sensation comes to terms with his date with a "legend".

Tsitsipas will meet 20-time grand slam winner Federer in the last 16 after defeating fellow seed Nikoloz Basilashvili 6-3 3-6 7-6 (9-7) 6-4 on Friday.

Seeded 14th, up-and-coming Tsitsipas is into the fourth round of a major for the second time in his career.

And the 20-year-old, who pushed Federer to two tie-breaks at the Hopman Cup in Perth earlier this month, is relishing his upcoming battle with the Swiss great in Melbourne.

"I learned a lot since my last match with him," Tsitsipas told reporters. "I know the patterns that he's using a bit better now.

"He's serving really well, so I'm going to have to utilise his, and take advantage of my returns as much as possible. I'm pretty sure he's going to be serving well, so, yeah, return games need to be aggressive and pressing a lot.

"He's a legend of our sport. It will be a great day facing him in one of the best arenas, Rod Laver. I'm really excited for that match."

Tsitsipas, who has enjoyed the overwhelming vocal support of the Greek community at Melbourne Park, added: "If I thought about it now it's insane I'm in this position where I can actually play him. It's really emotional."

Asked if he is ready for the showdown, Tsitsipas said: "It's not easy to play these kind of players that you've been watching for so long and you finally get to play them. Mentally you have to be much stronger than any other match that you have faced that week.

"Having such a name like Federer on the other side, it's an extra, I would say, advantage for him, because he's done what he's done. But mentally, for players to beat him, they have to be ready and believe in themselves that their game is great enough to beat such a player."