Manchester United legend Paul Scholes admits even Sir Alex Ferguson would knock before entering the club's dressing room.
Scholes wrote in the London Evening Standard: "If you want a measure of how private a place the dressing room was when I was growing up at Manchester United, consider this: even Sir Alex Ferguson would knock before coming into the dressing room at the Cliff, the old training ground. The dressing room is for the players, and the players only. It was a rule respected by all the staff at Old Trafford.
"In my final couple of years at United we had one player, new to the team and young, who posted a picture from the dressing room on Instagram or Twitter.
"I won't embarrass him by naming him because that too would contradict the rules about what stays private. Safe to say, the manager went ballistic and the player never did it again."
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