Writing in a foreword to a revised book on Cowdenbeath FC, the former fearsome Manchester United boss says he had to be rescued during the attack sparked by an on-pitch feud between him and rival player Andy Kinnell.
Sir Alex tells in the book Black Diamonds and the Blue Brazil - written by Church of Scotland minister Ron Ferguson - of the assault.
"In 1970, Falkirk won the second division championship and Cowdenbeath were runners-up," he reminisces.
"The games between the two teams were titanic. In one of the games at Central Park, I was up against Andy Kinnell, the Cowden centre half, who used to kick lumps out of everybody.
"We had a running battle through the game. In the tea room after the match, I was attacked by the tea lady. 'You hit my boy,' she said to me. She was Andy Kinnell's mother.
"I was rescued by Andy Matthew, the Cowden manager, who pretended there was a phone call for me."