You may be wondering, what's it like to play against the best tennis player in history?
Well, Nick Kyrgios has given us an inside scoop on what it is like to play against Roger Federer, who in case you didn't know, has been crowned six-time Australian Open winner and has amassed a total 20 Grand Slam titles throughout his career.
Working as a commentator on Australia’s Channel 9, the 23-year-old Aussie joined Jim Courier in the booth to run the rule over Federer as the Swiss star breezed past Taylor Fritz in straight sets.
Federer was at his best once again, serving with terrifying accuracy and constantly putting pressure on his young American opponent, as the 37-year-old comfortably triumphed 6-2, 7-5, 6-2.
"It’s so uncomfortable," Kyrgios said, as per The Metro.
"He puts the pressure right back on you. He shrinks the court so you feel like you can’t play. It never looks like Federer is fazed. Even if he hits a double fault, he always looks so relaxed.
"He’s so creative, he doesn’t even have to hit a conventional volley, he can hit swing volleys. He’s so creative, so talented.
"Federer’s timing is scary good. He almost hits everything on the half-volley.
"He’s always inside the baseline looking to come forward. He’s such a surgeon. It’s more the unknown with Federer. You think you know what’s coming but you don’t.
"He’s the greatest of all time. You’re not going to get many chances against Roger, when you get them you have to take them."
Tsitsipas, who played shortly before Federer and Fritz, admitted that he would have preferred to face the American in his post-match interview: "I mean, I've faced both of them.
"If Roger wins, it’s going to be amazing playing in Rod Laver.
"But I really hope Taylor wins," he laughed.
Unfortunately for him, he will meet Federer in the next round of the Australian Open in what promises to be a tremendous match-up.