Tottenham's FA Cup quarter-final against Bolton has been abandoned after Bolton midfielder Fabrice Muamba suddenly collapsed and had to be carried off on a stretcher.
With the game locked at 1-1, Muamba collapsed near the halfway line and play was suspended after 41 minutes.
Amid worrying scenes, six paramedics raced across the pitch and appeared to try to resuscitate the former England Under-21 international.
Referee Howard Webb made the decision to cancel the game after the incident.
Bolton boss Owen Coyle also joined the paramedics as they tended to Muamba and players from both sides looked visibly upset as the midfielder received treatment.
Muamba, 23, was carried off on a stretcher after receiving six minutes of treatment.
He was wearing an oxygen mask and was flanked by a number of paramedics and Bolton medical staff as he left the pitch.
Bolton confirmed he had been taken to hospital in a statement on their official website.
It read: "Bolton Wanderers can confirm that Fabrice Muamba has been taken to hospital following his collapse at White Hart Lane this evening during the FA Cup quarter-final.
"There is no further information at this stage."
Commentating on ESPN, John Barnes said: "From the players' reaction on both sides it seemed that things were pretty serious."
Kevin Keegan added: "Jermain Defoe seemed absolutely distraught.
"The fans are in a state of shock. I've never seen anything like that on a football pitch before.
"Our hearts go out to his family."
A host of footballers, including Tottenham's Jermain Defoe and Rafael van der Vaart and Muamba's Bolton team-mate Stuart Holden, took to Twitter on Saturday evening to wish the player well.