The 23-year-old Bolton Wanderers midfielder was fighting for his life after sinking to the turf during the FA Cup quarter-final at White Hart Lane, forcing the match to be abandoned soon afterwards.
The harrowing scenes were the latest chapter in a career that had seen the popular Kinshasa-born youngster defy improbable odds to build a new life for himself alongside some of the world's top stars in the Premier League.
Muamba arrived in England in 1999 as an 11-year-old schoolboy, joining his father who had fled DR Congo for London in 1994 seeking asylum fearing persecution in his homeland.
Despite not knowing English, Muamba thrived at secondary school, taking A-Levels while excelling at football.
"It was December 6, 1999," Muamba told The Daily Mail in a 2008 interview. "I was 11. Oh my God, it was so cold. I was shivering.
"I thought to myself: 'What am I doing here?' It was amazing the family being together again, but I couldn't speak a word of English. I did extra work at school and that helped me.
"My first day at school was just a big puzzle. There was nobody who was from the Congo. I did OK in French! But that was about it. People were talking too fast and I was just puzzled.
"PE was my favourite lesson. I used to like that because I used to run the show. Football was the answer to everything. That's how I got respect at school.
"People would say: 'That kid's good'. I didn't play for the district team. I just played for Arsenal's academy."
Starting a new life in England was relatively straightforward for Muamba however given his precarious upbringing in his strife-torn homeland.
"It was very, very tough," he recalled "I saw the war. I saw people die. I grew up with it. It was scary.
"I didn't live far from the gunshots and the sound of them going off. It was difficult to get used to, especially hearing guns at night. It did have an effect on me.
"It stopped us going out to play football because we were scared we would get killed. One or two of my friends were hurt, one or two of them have since died."
Safely in England, Muamba came to the attention of Arsenal, where he signed as a schoolboy in 2002 before being taken on as a professional in 2005, making his debut in a League Cup tie against Sunderland the same year.
Opportunities to break into Arsenal's star-studded first team were few and far between, however, and in the 2006-2007 season he headed to Birmingham on loan before joining them permanently in a £4 million deal.
While forging a career in professional football, Muamba also found the time to enroll on an Open University degree course in maths and data studies, joking that he wanted to gain a doctorate in order to be known as "Dr Muamba."
He joined Bolton in 2008, becoming a firm favourite with Wanderers fans for his whole-hearted style.
Qualifying to represent England at international level, Muamba played for several England junior teams before becoming an integral part of the country's Under-21 side, playing at last year's European Championships in Denmark.
Muamba spoke of his pride in playing for England before the tournament.
"This is my adopted country," he told an interviewer.
"People have helped me, welcomed me with open arms and given me this opportunity. I'm earning a more than decent living and leading a comfortable life. I'm very appreciative of that.
"When I hear the anthem, I just think about how far I have come. English people have helped me and I feel part of it."
Source: AFP
Source: AFP