Just a few minutes earlier, the 22-year-old had missed a penalty to condemn Les Bleus to a last-16 exit from Euro 2020 that looked impossible when they held a 3-1 lead against Switzerland entering the last 10 minutes of the game, only to let slip the two-goal advantage.
Mbappe was the fifth French spot-kick taker, but when goalkeeper Yann Sommer saved his shot, the world champions' tournament was over. Now, in front of coach Didier Deschamps, the rest of the staff and his teammates, Mbappe apologised. There was sadness in his voice, he was distraught. It was far from the arrogant image he can sometimes convey.
On his phone were tens of messages. From his dad, of course, who was in the stands and had an argument with Adrien Rabiot's mother, when she opined that Mbappe junior was arrogant. There were others: A couple from France president Emmanuel Macron, who wanted to console the forward, and from the likes of Arsene Wenger, Paris Saint-Germain president Nasser Al-Khelaifi and club teammate Neymar.
Mbappe also said sorry on social media, via a message sent around 3 a.m. His family was allowed to visit the France team hotel and other players also had visitors, but the atmosphere was gloomy. All that talent and a waste of a tournament. Deschamps tried to stay positive, saying: "Respect yourselves. Never forget what you have achieved before," but it meant little to his hurting stars.
This was supposed to be Mbappe's tournament and he badly wanted it to be. He has grown so much from the promising wonderkid, who lit up the 2018 World Cup final with two goals, and wanted to show that he could own an entire competition, but the stat line -- no goals and one assist in four games, with France winning just once and exiting early -- is unflattering.
But while the figures do not lie, they do not reflect the whole picture. Mbappe was very good against Germany, gifted the biggest chance of the game to Karim Benzema against Hungary and had good moments against Portugal, including winning a penalty.
He was involved in France's first two goals against Switzerland, with an assist on the first and a great back heel to play in Antoine Griezmann to lay on the second. So much more was expected, however, and he should have done better. He will, for instance, think for a long time about the chance he had in extra time, when he unexpectedly shot with his left foot and the effort went wide.
So what happened? Was Mbappe too confident? Probably, but that is his strength. Did he put too much pressure on himself? He relishes the big moments and wanted them at this tournament. He wanted to be the star. He wanted to be the one taking the decisive penalty.
Did he not have the right attitude? He was frustrated by Olivier Giroud's pre-tournament comments, when the veteran striker hinted Mbappe was not passing him the ball, and spoke to the media in a press conference to express his feelings.
The departure through injury of his best friend in the squad, Ousmane Dembele, was another setback and sources have told ESPN that Mbappe was occasionally on his own, slightly apart from the group. His in-game partnership with Karim Benzema was France's best asset, but maybe their off-pitch relationship was too strong and they isolated each other from the rest of the squad.
Was he tired? He felt weary against Portugal and looked exhausted at the end of normal time against Switzerland, but he might not have been the only one; Deschamps is already looking at what went wrong and under scrutiny is the heavy fitness work done before the start of the tournament.
Did uncertainty over his club future play on his mind? In the next few weeks, Mbappe will opt to stay at PSG -- and extend the contract that expires after next season -- or leave. He will take his time to decide and is talking to Al-Khelaifi directly about the situation, but what is certain is that, had there been an earlier resolution, it would have been one fewer possible distraction.
Mbappe will take this experience like a failure and, not only does he hate to fail, he is not used to doing so. Since his debut as a 16-year-old at Monaco, he has succeeded in pretty much everything, but not this time. In that, though, he was far from alone; France had other issues.
Mbappe cannot solely be blamed for the early, embarrassing exit, even if he missed the final penalty. Yet the criticism directed toward him is part of the process for a top player. After all, he was dreaming of a great tournament, with goals and performances to put his name right at the top of the Ballon d'Or candidates, and much was expected.
His private plane was ready for him and his family to go on holiday. He needs a rest after a draining season that effectively began on the same day as the previous one ended. There are questions that need to be answered, but for now, Mbappe will take a proper break and try to forget about football and Euro 2020.