One of the tournament's favourites the Netherlands suffered a shock defeat to Denmark in their opening match of the Euros on Saturday.
The Danes took the lead in the first half through the impressive midfielder Michael Krohn-Dehli who drifted away from two defenders to fire home the winner.
Up until that point the Dutch had been dominant and remained so until the final whistle. They had numerous attempts on the Danish goal but it just wasn't their night with star strikers Robin van Persie and Arjen Robben uncharacteristically rusty up front.
However, despite the poor finishing of the Dutch, the Danish team should be credited for their determined display.
Before kick-off Denmark were rank outsiders to progress from Group B but on this occasion were equal to their opponents in defence and will provide a tough challenge to group rivals Germany and Portugal.
It was Krohn-Dehli who provided the lethal finishing the Dutch inexplicably lacked.
Krohn-Dehli scored against the run of play when he picked up a loose ball close to the penalty area in the 24th minute, left two defenders standing and shot through the legs of Maarten Stekelenburg from a tight angle.
It was something Premier League top scorer Robin van Persie never got close to as he came to symbolise Dutch futility with a couple of bad mistakes.
Denmark goalkeeper Stephan Andersen made several clutch saves to secure the most important Danish victory over the Netherlands since the Euro 1992 semifinals.
"Five of us had chances...Once we hit the post. So many good opportunities"
Netherlands captain Mark van Bommel
"It was the only dangerous action of Denmark,'' Netherlands captain Mark van Bommel said.
"I'm speechless, because these three points are very important.''
The Dutch came closest to scoring when Andersen gave away the ball to Arjen Robben just outside the area in the 36th minute, but the Bayern Munich winger curled his left-footer onto the far post and out of danger.
"Five of us had chances,'' Van Bommel said.
"Once we hit the post. So many good opportunities.''
The frustration came to symbolise the sticky night in eastern Ukraine and leaves the World Cup runners-up with two clutch games against top-10 ranked teams, Germany and Portugal.
Late in the match, a penalty appeal for handball was denied when the Dutch were running out of time as Lars Jacobsen appeared to touch the ball with his upper arm in the box.
Denmark, seen as outsider in the toughest group of the championship, can already take a huge step to the quarterfinals by beating Portugal in their second game.
"We know the Dutch, they can be very dominating,'' Denmark coach Morten Olsen said.
"If you get scared of them, they play really good football. I think we played them in the right way.''