Joao Fonseca revelled in his "crazy" five-set win over Novak Djokovic at the French Open, but still reaffirmed that the 24-time grand slam champion remains the "GOAT". 

Fonseca booked his place in the fourth round at Roland-Garros in some style, coming from two sets down to earn a seismic 4-6 4-6 6-3 7-5 7-5 victory in just under five hours. 

By doing so, the Brazilian became just the second teenager in the Open Era to defeat Djokovic, who has won the French Open title three times, at a grand slam event. 

He also became the first teenager to defeat a former men's singles champion at Roland-Garros since Andy Roddick, who beat Michael Chang in the second round in 2001. 

Fonseca will now face Casper Ruud, who himself came from two sets down to beat Tommy Paul to progress, but he was keen to take in the moment after his win over Djokovic. 

"Crazy experience for me," Fonseca told TNT Sports. "It was difficult to sleep before the match. Just stepping on court was the first time hitting with him. We had never practised. 

"I was just trying to be grateful and play my best. After the second set, I was not believing in my game, and he was destroying me and when I won the third set, I started believing.

"Djokovic is for sure an idol for this sport. Him and Roger [Federer]. I am a Roger fan, but I know Djokovic is the GOAT. I wish it could be Roger, but that's life. 

"It was difficult to realise when I finished, did I really win? In the fifth set I wasn’t thinking at all, I just played."

Fonseca's run to the fourth round is the furthest he has ever gone at a major, having lost in the third round at Wimbledon to Nicolas Jarry in straight sets last year. 

And he appeared set to fall at the same hurdle in the French capital after finding himself 3-1 down in the decider as Djokovic took control of the match in the closing stages. 

However, the 19-year-old rallied back and reeled off the final three games, sealing his famous victory with three consecutive aces that flashed past his opponent. 

Asked how he managed to get back into the match after dropping the first two sets, Fonseca added: "Actually, I was not even believing myself.

"I mean, it was tough to play against him in the heat. He was destroying me.

"If I hit it hard, the ball comes back harder. If I would go higher, he would just do drop shots and go aggressive.

"I just stayed focusing on point by point, not focusing on that I had three more sets to win. I was just thinking, 'let's stay, let's stay'.

"I figured out he was a little bit more tired, and that gave me a little bit more hope. When I won the fourth set, I was already tired. The fifth set was all heart. I couldn't even think."