A day after Denmark midfielder Christian Eriksen collapsed on the pitch, team doctor Morten Boesen revealed the severity of the incident.
"He was gone, and we did cardiac resuscitation. It was a cardiac arrest," Boesen said, speaking to reporters on Sunday. "How close were we [to losing Eriksen]? I don't know."
Boesen said he was revived "after one defibrillator," which he remarked was "quite fast."
The 29-year-old, who has represented Denmark nationally since 2010, is in stable condition at a hospital in Copenhagen.
This article will be updated to provide more information on this story as it becomes available.