England and Nottinghamshire batsman James Taylor admitted his world was "upside down" after being forced to retire at the age of 26 because of a serious heart condition on April 12, 2016.
Here, the PA news agency looks back at the news which rocked cricket.
What happened?
He said on Twitter: "Safe to say this has been the toughest week of my life! My world is upside down. But I'm here to stay and I'm battling on! #lifestooshort.
"Absolutely overwhelmed with all the support I've received. You don't understand how much it means to me and how much it helps! Thank you!"
How the sporting world responded
Nottinghamshire director of cricket Mick Newell told the players of the news before the third day of their Specsavers County Championship opener against Surrey, a match Taylor initially pulled out of due to illness.
Newell spoke of the shock of everyone at Trent Bridge, saying: "Myself and all of James' team-mates and colleagues are terribly sad to hear this news, which comes as a big shock to us all.
"He is a model professional, the most hard-working I've ever known in cricket, making it all the more difficult to accept that his career has been cut short in this way.
"I think the initial devastation (of being told) you aren't going to play cricket was then tempered by how grateful he is to be alive so that's probably why he perked up a little bit.
"They (the doctors) have been telling him that quite a lot of the time they don't find out about this illness until it is too late."
Muamba is one of small number of professional sportsmen who have had to retire in similar circumstances – including Wales rugby union front-rower Rhys Thomas, also in 2012, and Ireland prop Simon Best.
The former footballer sent his own to Taylor message, via Twitter: "@jamestaylor having life is a great option. Retirement is inevitable, but for some of us it's just earlier than expected. Enjoy life."
Taylor replied: "Look forward to hopefully meeting you one day mate! #inspiration"
His England team-mate Chris Jordan made clear how badly Taylor's presence as a colleague will be missed.
"When I woke up to that news this morning, I was a little bit lost for words," the Sussex seamer told Sky Sports News.
"But I think that, in times like these, it's more important to think about him as a person ... around the dressing-room, he was a real livewire and a real good guy to have around.
"I really do wish him all the best."
Life after retirement
Taylor made an initial move into broadcasting, joining the BBC's Test Match Special team.
But in 2018 he was named a a full-time selector for the England team, by the recently-appointed national selector Ed Smith.
