But who is the goliath-slaying Queenslander? With the bad behaviour of many Australian tennis stars regularly dominating the headlines, it’s hard to fathom that one of our greatest hopes has flown under the radar for being, well, a good bloke.
Well while the likes of Tomic have been wreaking havoc on Australian tennis, 29 year-old Millman has been training, practicing and preparing for his moment, which seemingly came this week in New York.
"I'm a big fan of John. Maybe not that many people know him but he's a real hard-working guy out there and those are the guys who have all the respect from us top players in the locker room," Federer said before the fateful match, in comments that may have changed since going down. In fact, it seems that Millman may be closer to the Swiss master than his Aussie counterparts, given his knack for winning and his nice-guy demeanour.
"He's just come to Switzerland to train with me before the grass-court season so we know each other quite well, a super friendly guy, and I'm very happy for him that he's gotten so far,” continued the 5 time US Open champion.
Despite never progressing further than the third round in a Grand Slam, Millman is no stranger to success on the court, having amassed US$1.8million in prize money over the course of his decade-long career. A conservative figure that hasn’t taken into account this week’s earning.
But it hasn’t all been winnings, and the illusion of an overnight success is extremely misguided. "It's been a long journey," Millman said following his win. "It hasn't come too easy for me and it's very cliche but this is why you play: to be competing at these famous tournaments."
"It's not for the money. It's for the opportunity to play these historic events. It's rewarding when you play good tennis and it's even more rewarding when you've had your struggles.” The struggles Millman refers to include shoulder surgery, as well as the associated recovery and working a full time job in finance whilst still chasing a career in professional tennis.
Even a recently as 2017, Millman was benched due to a hip injury, which took him out of action for a solid 5 months.
"We all know that's been documented. I don't really like to harp on it too much, but it does feel more rewarding when you have your struggles and you work really hard and the guys around you work really hard to get you back and you can do it for them a little bit."
"It took me a long time and I'm sure there were times during those tournaments where I questioned whether I really wanted it. But it makes you really appreciate these moments even more."
After the epic Federer match at Arthur Ashe Stadium, which stretched into the early hours of the morning, Millman will now face Novak Djokovic in the quarter finals.