At 20 years old, Stefanos Tsitsipas recorded possibly the biggest win of his young career as he knocked defending champion Roger Federer out of the Australian Open in the fourth round.

Upsetting the established stars isn’t new to Tsitsipas. He had earlier beaten Novak Djokovic, as well as Alexander Zverev, Dominic Thiem and Kevin Anderson at the Roger Cup in August last year.

But his 6-7 (11-13), 7-6 (7/3), 7-5, 7-6 (7/5) win over the 37-year-old Federer at the Rod Laver Arena will be the most sentimental victory given that it came over a player he has idolised ever since he was six.

Just how much did the Green youngster look up to the 20-time Grand Slam champion? Enough to change his double-handed backhand to a single-handed one to emulate the Swiss star.

An old video doing the rounds on Twitter after his win on Sunday night gave another glimpse of this. Uploaded by Alex Theodoridis on Twitter, the footage from the Royal Tennis club in Stockholm and Kungens Kanna showed the teen talking about Federer, his favourite idol.

Tsitsipas also spoke about how his biggest weapons were his backhand and volley, both of which he used to good effect in his win over Federer.

Also read: Fearless on and off the court, Tsitsipas signals arrival by outplaying idol Federer

The social media philospoher, who writes his own motivational quotes and has his own YouTube channel, a podcast and an Instagram page for still photography, showed his big-thinking when asked where he sees himself in 10 years.

“I don’t know, but I will do my best to be in the top,” he said.