Tottenham's FA Cup quarter-final against Bolton was abandoned by referee Howard Webb just before half-time after Bolton midfielder Fabrice Muamba suddenly collapsed and had to be carried off on a stretcher.
With the game 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.
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.
Both sets of fans sang Muamba's name as he lay on the pitch at the north London ground.
The announcement that the game had been called off was greeted with a round of applause from both ends. Bolton are expected to give an update on Muamba's condition later this evening.