“He was gone. We did cardiac resuscitation, it was a cardiac arrest,” he told a press conference arranged by the Danish football federation.
“How close were we to losing him? I don’t know, but we got him back after one defib, so that’s quite fast.”
Boesen said it was still unclear why the 29-year-old collapsed but added that Eriksen may not have survived if the game had not been played at a major soccer tournament with top-class medical equipment at hand.
“That was completely decisive, I think,” Boesen said. “The time from when it happens to when he receives help is the critical factor, and that time was short.”
Watch: Football world reacts after Christian Eriksen collapses at Euro 2020
He said he now feels the game should not have resumed around 105 minutes after the incident, and revealed that a psychologist was brought in to help Denmark’s players and staff on Saturday night.
“I don’t think the right decision was to play the game,” Boesen said. “We have had help from a psychological point of view at the hotel last night. Everyone expressed their feelings and how they saw the situation, and everyone was pleased we did this and talked it through.
“We really appreciated the professional help we have had from the outside.”
Denmark manager Kasper Hjulmand agreed that they should not have carried on with the match but said the squad would try to use what happened as motivation for their next game against Belgium on Thursday.
“Looking back, I honestly don’t think that we should have been back on the pitch,” Hjulmand said. “I have thought about whether I could have done things differently.
“We will try tomorrow to establish normality as much as possible. Players have different reactions to shocks and trauma but we will try to get back to normal as much as possible.
“I get the feelings from the players that maybe the time is too short to try to play football again, but maybe we can use it as a force to get together and try to go out and do our best in the next match.”
Watch: Fans chant in support of Christian Eriksen after footballer collapsed on pitch
Eriksen is in stable condition in a Copenhagen hospital and has been in contact with the rest of the Denmark squad via video conference.
Hjulmand said: “Christian is in good spirits and it’s a huge relief for the players after all this uncertainty,” Hjulmand added. “There is no doubt that we have been on the ropes.”
He quoted the player as saying: “I don’t remember much but I’m more concerned about you guys. How are you doing?”
Hjulmand added: “That’s typical Christian. It was good to see him smile.”