Tottenham's FA Cup game against Bolton Wanderers has been abandoned after Trotters midfielder Fabrice Muamba collapsed and stopped breathing.
Medics spent 10 minutes trying to resuscitate the 23-year-old on the field before the players were taken off by referee Howard Webb.
BBC Radio 5 live senior football reporter Ian Dennis says the English midfielder is fighting for his life.
The score was 1-1 when he collapsed with no players close-by on 41 minutes.
Medical staff gave Muamba mouth-to-mouth resuscitation and tried to revive him with a defibrillator. In total six medics were treating the player.
Both sets of supporters chanted Muamba's name as he was taken off the pitch on a stretcher. ESPN reported that he was not breathing as he was taken down the tunnel.
The former Arsenal midfielder has been taken to hospital, accompanied by manager Owen Coyle and club captain Kevin Davies.
A Bolton spokesman said: "Fabrice Muamba has been taken to hospital following his collapse. There is no further information at this time."
Referee Webb called the visibly shaken players off the field after consulting with Coyle and Tottenham boss Harry Redknapp.
Minutes later the match was abandoned.
Soon after the incident, messages of support flooded in for the former Arsenal man.
Spurs player Rafael van der Vaart was one of the players on the pitch when Muamba collapsed. He tweeted: "Terrible what happened with Muamba during the game. We're all praying for him."
England international Jack Wilshere, who played with Muamba at Bolton, tweeted: "Hope Muamba is okay. Thoughts with him."
Middlesbrough defender Justin Hoyte, who played in the Arsenal youth team with Muamba, said: "I seriously hope my best friend in football is OK. Stay strong bro [sic] please please stay strong. God is with you remember that."
PFA chief executive Gordon Taylor said: "At the moment we are all watching, waiting, hoping and praying. For all the football family it's a terrible thing to see.
"We just hope it's not going to be a situation like that of Marc-Vivian Foe.
"This can happen on a pitch and one of the reasons why we insist all youngsters coming into the game have the ability to have heart screenings to avoid this happening."
Muamba joined Wanderers from Birmingham City in 2008 and has made 130 league appearances for the club.
BBC SportPublished Date: 2012-03-17 12:35:33 GMT