Only Romelu Lukaku knows what was going through his head in the minutes after his friend and Inter Milan team-mate Christian Eriksen collapsed during the Group B opener between Denmark and Finland.
The same goes for Jan Vertonghen and Toby Alderweireld who have spent most of their careers playing alongside Eriksen at Ajax and Tottenham.
As the world anxiously waited for news on Eriksen, just imagine how the three Belgians were feeling as they tried to prepare for their country's first group game against Russia in St Petersburg.
A year's delay for Euro 2020, months of build-up, weeks of preparation and suddenly they were in turmoil as the horrific events unfolded in Copenhagen.