In their first match since Christian Eriksen suffered a cardiac arrest on the pitch, an inspired Denmark scored the second-fastest goal in European Championship history when Yussuf Poulsen netted after 99 seconds.
Kevin de Bruyne came off the bench at halftime to set up the equaliser, however, before smashing home an emphatic winner which sent Belgium into the knockout stages with six points from two games.
“The fans created an incredible atmosphere. The fans gave the home team a one-goal lead and at that point we were a little bit shell-shocked,” Martinez told reporters after a match which included a minute’s applause for Eriksen in the 10th minute.
“It took us probably 20 minutes to start being ourselves again but we couldn’t get that desire, heart and pressure that the Danish team had. I felt that in the first half, there was a lot of emotion involved.
“The second half was totally rational, we showed incredible character, big hearts and (played) with a real idea of what to do. This is the victory that you enjoy and treasure, it makes you better as a team.”
De Bruyne was playing his first match since he went off injured in last month’s Champions League final and Martinez praised the Manchester City midfielder who has recovered from a double facial fracture.
“You never doubt his talent. Obviously, it’s a big ask to come on halftime and be able to affect the game the way he did,” Martinez said.
“The way he played in the second half, he didn’t look like a player that has been through surgery and has been away from the football pitch. It shows you the way he looked after himself, the way he was focused in training.
“This was a very impressive way for a player away for a long time to introduce himself and affect the game in that way.”