England launched their bid for Euro 2020 glory with a 1-0 win over Croatia on Sunday as Denmark's team doctor confirmed Christian Eriksen had suffered a cardiac arrest and was "gone" before being resuscitated.

Raheem Sterling scored at a sun-baked Wembley as England won their opening game of a European Championship finals for the first time at the 10th attempt.

But the action on the pitch was overshadowed by the fallout from the shocking events in Copenhagen's Parken Stadium the previous day.

Inter Milan star Eriksen suddenly collapsed in the 43rd minute of Denmark's Group B game against Finland, lying motionless as medics administered CPR and the crowd looked on aghast.

The game was temporarily suspended awaiting updates on Eriksen's health, but resumed later in the evening after reports filtered through that the player was in a stable condition and awake. It ended in a 1-0 win for debutants Finland.

"He was gone, and we did cardiac resuscitation, and it was cardiac arrest," team doctor Morten Boesen told a press conference on Sunday, adding that so far there was no explanation for what had happened.

"How close were we? I don't know. We got him back after one defib (defibrillation), so that's quite fast."

Denmark's players gather as medics treat midfielder Christian Eriksen during the Euro 2020 match against Finland
Denmark's players gather as medics treat midfielder Christian Eriksen during the Euro 2020 match against Finland POOL / WOLFGANG RATTAY

Players in the Danish team were given the option to continue the game or postpone the match but head coach Kasper Hjulmand said he regretted the decision to carry on.

"I honestly don't think that we should have been on the pitch again," he said.

Denmark forward Martin Braithwaite called the incident "one of the scariest moments of my life".

"I'm grateful that he's stable and alive. Right now, that's all that matters. Hope to see you soon my friend," he tweeted.

Manchester City's Sterling scored his first goal at a major tournament as England gained a measure of revenge for their 2018 World Cup semi-final defeat by Croatia.

The forward's sharp finish in the second half was enough for the home side to send the Wembley crowd home happy.

England forward Raheem Sterling celebrates his goal against Croatia
England forward Raheem Sterling celebrates his goal against Croatia POOL / Catherine Ivill

Sterling grew up in the shadow of London's Wembley and justified manager Gareth Southgate's decision to keep faith with him by scoring the only goal just before the hour.

"I always said if I played at Wembley in a major tournament, I'm scoring. I had to score in my back garden and delighted to do that," he told the BBC.

Southgate said: "I'm so pleased for Raheem, he's had this hex in the tournaments. I felt he was dangerous all day. Right from the start he looked a threat."

There were fears before the match that supporters would boo players for taking the knee to protest against racial injustice as they had done before pre-tournament friendlies.

There was a smattering of jeers from sections of the 22,500 crowd, but the majority cheered the gesture.

England, seeking to end a 55-year wait for a major trophy, are playing all three group games at their London home. If they top Group D they will also play there in the last 16, while London is also the venue for both semi-finals as well as the final on July 11.

The Netherlands, back at a major tournament for the first time since 2014, play Ukraine in Amsterdam on Sunday, deprived of the services of the long-term injury absentee Virgil van Dijk but still able to call on a wealth of talent including Barcelona midfielder Frenkie de Jong.

Ukraine's pre-match preparations have been marred by a row with Russia over their jersey that features patriotic slogans and the outline of Ukraine that includes Crimea, which Russia annexed in 2014.

North Macedonia lost 3-1 to Austria in their first match in a major tournament as an independent nation in Bucharest, despite an equaliser from 37-year-old captain Goran Pandev.

The coronavirus, which delayed the tournament for a year, is still proving a major headache.

Portugal defender Joao Cancelo has tested positive for Covid-19 and is out of Euro 2020, the defending champions announced.

Diogo Dalot has replaced the Manchester City right-back in the Portuguese squad, with the titleholders opening their Group F campaign against Hungary in Budapest on Tuesday.

The Russian, Spanish and Swedish squads have also been hit by positive tests.

World Cup holders France -- with Karim Benzema recalled from a five-and-a-half-year international exile -- are the favourites to win the continental crown.

They begin their campaign against Germany in Munich on Tuesday, also in Group F.