Roy Hodgson says Fabrice Muamba's collapse last weekend stirred painful memories of when one of his own players suffered a cardiac arrest on the pitch.
Current West Brom head coach Hodgson was in charge of FC Copenhagen when midfielder Stale Solbakken, then aged 33, collapsed during a training session.
Hodgson said the former Norway international was pronounced "clinically dead" but eventually made a full recovery although it marked the end of his career.
The manager said: "When I was at FC Copenhagen, exactly the same thing happened as with Muamba. It was a complete parallel.
"His heart stopped, he was clinically dead for a period of time. It happened on the training ground and we feared the worst when he left the training ground.
"As has happened at Bolton with Owen Coyle, the club shut down for three days.
"We had three days desperately waiting to hear news, what was going to happen, and when he was eventually going to be woken from the coma, what we would find?
"We waited to find if he would be fully recovered or had some major defect as a result of his heart stopping for that period of time.
"I remember how relieved and happy we all were when Stale woke up and started talking and the doctors told us there was no brain damage and he would be fit again.
"I am pleased to say Stale completely recovered 100% and has gone onto be a very successful coach and I only hope it is the same with Fabrice."
Hodgson added: "Stale didn't play again. Fabrice is a lot younger. Stale was 33 at the time. He had the pace-maker fitted but didn't play again on doctor's advice. That might not happen with Fabrice who is a lot younger.
"With Fabrice I know no more than what I hear on the news, but it all seems very positive and we are all very happy about that.
"Having experienced that myself, albeit in a training session, I can assure you it is not an experience you want.
"It is an experience which is a very chastening one and whenever people's lives are in danger in football, it makes you question where football really is in the grander scheme of things."