Brazilian teenager Fonseca produced a sensational comeback to erase a two-set deficit and beat Djokovic 4-6, 4-6, 6-3, 7-5, 7-5 after almost five hours on court.

Djokovic was condemned to his earliest exit at Roland Garros since 2009, and left the court making a heart gesture to the Philippe Chatrier crowd.

Asked if he would be back next year, Djokovic twice replied: "I don't know."

Djokovic has been stuck on 24 majors since the 2023 US Open and may not get a better chance to add to that haul.

The 39-year-old, a three-time winner at Roland Garros, had once more emerged as the man to beat following the shock exit of world number one Jannik Sinner.

Two-time defending champion Carlos Alcaraz was already missing in Paris due to injury.

But Djokovic was in no mood to reflect on what might have been.

"I don't care. I don't care. I'll stop you right there. No. Just lost third round. Let's just talk about something else," he said.

There will be a first-time men's Grand Slam champion this year at the French Open, ending a run of nine successive majors won by Sinner or Alcaraz.

Djokovic said Fonseca had clearly shown why he was so highly rated despite struggling for consistency this season.

"I congratulated him and told him that he deserved to win and played an unbelievable match, and he should be proud of himself," said Djokovic.

"The kind of level of tennis we've seen him play created a lot of hype around him, and I think we've all seen today why there is hype around him. The level was amazing."