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The 19-year-old fought from two sets down to knock out Novak Djokovic in the third round and emerge as a genuine contender in a topsy-turvy tournament, and his latest victory highlighted his growing confidence and composure on the biggest stage in Paris.

"It was tough, Casper plays good here, I mean he's a very experienced guy and he knows how to play here in this amazing court," Fonseca said after the win.

"It was tough in the beginning but I played really well in the important moments in the first and second sets. I was very happy because of that.

"I just try to be me on court, try to be happy, try to hit winners, try to hit good shots and bring entertainment."

Playing on Court Philippe Chatrier again, Fonseca sparkled under the lights with some spectacular ball-striking from both flanks and broke in the 12th game to wrap up the first set and draw huge applause from fans.

After an early exchange of breaks in the second set, Fonseca and Ruud were locked in a titanic tussle of power hitting, until the Norwegian squandered three set points and allowed his young opponent to edge an electric tiebreak.

It left Brazilian three-times Roland Garros champion Gustavo Kuerten beaming as a raucous crowd roared, but Ruud was not done and snatched the third set to ensure the entertaining encounter would trickle into the early hours of Monday morning local time.

"He's an idol for our sport and country, for his charisma and how humble he is," Fonseca said of Kuerten.

"He was here for my first time at Roland Garros when I was a junior. It is a pleasure to have him here and a pleasure to beat a tough opponent in front of him."

Fonseca raised his level again in the fourth, claiming a double break as the atmosphere reached fever pitch, before world No.30 closed out another famous victory and booked a meeting with Czech Jakub Mensik.