After a disciplined first-half performance from the visitors, Jonas Wind’s 47th-minute strike put the Danes ahead and Northern Ireland thought they had secured a late point through debutant Callum Marshall, but after a lengthy VAR review, it was ruled out for offside in the build-up.
Here are the best Northern Ireland fan photos from Copenhagen. The gallery will be updated as more images become available.
5. Fans at the stadium
Northern Ireland fans at the stadium Photo: Jonathan Porter / Press Eye
6. Living every kick
Northern Ireland fans watch on as their team play Denmark in Copenhagen Photo: Jonathan Porter / Press Eye
7. Cheering on their team
Northern Ireland cheer on Michael O'Neill's side in Copenhagen Photo: Jonathan Porter / Press Eye
8. Come on Northern Ireland!
Northern Ireland fans in the stadium Photo: Jonathan Porter / Press Eye