Despite losing their first two games of the tournament, an inspired Danish side thumped Russia in Copenhagen to secure a last-16 spot.
Mikkel Damsgaard opened the scoring with a stunning strike in the 38th minute. Yussuf Poulsen then made it 2-0 in the early stages of the second half as the Russians crumbled.
With 20 minutes remaining, Stanislav Cherchesov's men were given a late lifeline after being awarded a controversial penalty.
Artem Dzyuba was able to convert from the spot to provide hope of a comeback.
Denmark, though, had different ideas. With ten minutes remaining, Andreas Christensen added a third before Joakim Maehle sealed a comprehensive victory with Denmark's fourth goal of the night.
Easy work for group winners
Over in St Petersburg, Belgium cruised to a 2-0 victory over Finland.
The Finns had everything to play for. However, that didn't reflect in the way they played.
After a slow and eventless first-half, the game did somewhat come to life in the second.
Unfortunately for Finland, it was their goalkeeper, Lukas Hradecky, who was credited with Belgium's opener. The Bayer Leverkusen man was caught off guard as the ball hit the post and bounced off his arm to cross the goal line.
Romelu Lukaku made sure of the three points with a goal in the final ten minutes of the contest.
The strike puts Lukaku on three goals - joint-top of the Euro 2020 score charts alongside Cristiano Ronaldo, Patrik Schick and Georginio Wijnaldum.
Stat of the day
From OptaJoe: "Denmark are the first team in European Championship history to reach the knockout stages of the competition having lost their first two group stage games."
Having won the group, Belgium will now take on one of the third placed teams from group A, D, E or F. Over the next few days, we will find out exactly which nation will cross paths with the Red Devils.
That round-of-16 clash will take place on Sunday, June 27 in Seville.
With regards to Denmark, after clinching a second-placed finish in their group, the team will now gear up for a clash with Wales. The game will take place on Saturday, June 26 in Amsterdam.
Wales also finished as runners up in their group but as recent performances showed, they're high on confidence under caretaker manager Rob Page.
Third-placed Finland, meanwhile, have a few possible options on the table.
One of those options is elimination as three points may not be enough to secure progression. However, if they are lucky enough to make the last-16 stage, they will either take on the winners of Group F (France, Germany or Portugal) or the winners of Group E (Sweden, Slovakia or Spain).