Tottenham defender Benoit Assou-Ekotto admits Fabrice Muamba's collapse at White Hart Lane will live with him forever.
Muamba is critically ill in a London hospital after undergoing a cardiac arrest during Bolton's FA Cup quarter-final with Spurs.
Some Spurs players were visibly upset at the 23-year-old's collapse and Assou-Ekotto has spoken of his shock at the incident, which reminded him of the game in which fellow Cameroonian Marc-Vivien Foe died in 2003 after collapsing on the pitch during a game in France.
"Saturday was one of those days that will stay with me forever," Assou-Ekotto wrote in his London Evening Standard column.
"When I saw him lying on the pitch at White Hart Lane, I was scared. Scared for him, scared for his family, his friends and all those people who know him and who care about him.
"I was also scared because he was just like me. He is young, supposedly fit - an athlete - who a few seconds ago was running up and down the same pitch as me. I had flashbacks of what had happened to my countryman, the late Marc-Vivien Foe.
"You want to stop these thoughts but the pictures keep coming into your head and I must say I was scared. Scared as I wondered how it could all just end like that for a young man? I could see the same questions in the eyes of my team-mates, the Bolton players, our bosses and their colleagues."