Muamba had a heart attack as he played for Bolton in March 2012 during a game against Tottenham Hotspur, and ultimately decided to retire from the game rather than attempting to make a comeback.
The former Arsenal player talked to the club's In Lockdown podcast, and described the interactions he had with Thierry Henry when the former Barcelona and Arsenal player was playing in New York.
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"They said it is nothing short of a miracle," Muamba explained. "I am fortunate that I am still here and even prior to the accident me and Thierry were talking on the phone, on messenger, and he told me, 'Just go out there and make sure you do well against Tottenham'.
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"I remember missing a good chance to score a goal and then I came to the halfway line and I felt very dizzy. Then... boom! It happened! To be fair to Thierry he was in New York then and he still came to see me.
"He came to see me and he came through the back entrance of the hospital. Don't get me wrong, most of the guys came through the front entrance but he came in through the back entrance and spent about 10 or 20 minutes with me.
"I remember saying hello to him but because I was so drugged up I couldn't recall everything. I remember speaking to him, then falling asleep, then him speaking to my dad. He literally spent 20 minutes with me and then he flew back home straight away.
"That was within the first three or four days. He came straight away. Thierry is a good guy."
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A second meeting in New York helped him make the final decision to retire.
"When I had to decide to stop I was going to New York for an event and I called him and said, 'I'm in New York' and he said, 'Come over'. So I went to his place and we had an open conversation and he gave me his honest opinion. He said, 'Listen, if you play you're not going to be sure [about your condition]. If you stop you're still going to be here so which is it? You decide.'
"That was his opinion to me. Yes. He put it on the table because I was adamant about going back and playing. It just makes sense: if he was saying it and other people were saying the same thing, then why not just make a decision? Then when I went to see the specialist, we decided that was it."
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