Phelan has lifted the lid on some of the selection techniques employed by the manager.
"Part of my job was to hold him back because he could come out with some very strange decisions at times," he told the Manchester Evening News, "I had to guide him through them and I managed to do that at times.
"And he probably wasn't the only manager to toss a coin to pick a player to leave them out! It is one of the hardest things for a manager to say to a player that they are not involved in a particular game after they have done a hard week's training.
"But he would toss a coin at times in situations like that. Big managers have to make big decisions and over a period of more than 20 years he made more right decisions than he did wrong ones."
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