UEFA investigates the fall of the English fan right after the game started in London at 2 o’clock in the afternoon.
“We can confirm that a spectator fell from the stands just after the kick-off of the match between England and Croatia at Wembley Stadium, ”a spokesperson for the pitch said in a statement.
“The spectator received medical treatment on the spot and was then taken to hospital in serious condition.
“We will continue to work with UEFA to ensure the matter is fully investigated and we continue to monitor the situation. “
There were 22,500 fans in the stadium, according to the government’s lockdown roadmap.
England won their first European Championships game – for the first time in history – after Raheem Sterling scored in the second half.
The fan incident comes a day after Danish player Christian Eriksen suffered cardiac arrest during his country’s match against Finland.
Authorities say he is now awake and in stable condition in a Copenhagen hospital.
Denmark Team doctor Morten Boesen told a press conference the 29-year-old was “gone” before medics started putting him back on the pitch on Saturday.
“How far were we? I do not know. We got it back after a defib, so it’s pretty quick, ”he said.
“We have no explanation why this happened. The details of what happened, I’m not quite sure because I’m not a cardiologist, I’ll leave that to the experts. I didn’t see it live, only on the screens afterwards. “
Team captain Simon Kjaer has been hailed as a hero as the first to rush to Eriksen’s aid after collapsing with no other players around him.
Eriksen, who had no history of heart problems, may no longer be able to play professional football, experts have suggested.
There were cheers ahead of England’s game against Croatia as the announcers wished Eriksen good luck.
A large screen displayed the message “Best Wishes Christian” as applause erupted from the stands.