The forward picked up the injury in the dying minutes of France’s 1-0 win over Austria in Dusselorf on Monday night.
Mbappe collided with defender Kevin Danso, resulting in a broken nose and a blood-stained shirt.
After lengthy treatment on the pitch he was subbed off and headed straight down the tunnel in worrying scenes for Les Bleus’ players and fans.
It was initially thought that with just a broken nose, Mbappe would be okay for the rest of the Euros, albeit he would likely have to wear a face mask.
But video footage later showed the France captain going into an ambulance and being taken to University Hospital of Dusseldorf.
Reports say that a decision will be made overnight on whether or not the 25-year-old will need emergency surgery which could rule him out for the rest of the tournament.
Speaking in his post-match press conference, France boss Didier Deschamps shared a worrying update on the player many consider to be the best in the world: ‘He’s not doing well. He’s with the medical staff.
‘His nose got badly hit, that’s for sure. We need to check it out, but it seems quite complicated. Which is very unfortunate for us tonight.
‘I don’t have the elements in my hands, the medical staff is checking him out. He didn’t get off lightly.
‘It’s still to be seen. And at this stage, I can’t answer [when he will return]. I don’t know. That’s the black mark from this evening.’
Former France team doctor Fabrice Bryand told L’Équipe du Soir that he thinks Mbappe will be out for at least 10 days, but also added ‘it could stop his participation in the Euros.’
Chelsea legend N’Golo Kante, who was named player of the match for France’s win, added: ‘We’re worried to see Kylian leave the field like that. It’s worrying. But we hope it’s not too severe and that he’s soon back with us.’
France are set to take on the Netherlands on Friday night before their final Group D match against Poland on 25 June.
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