Moyes is good friends with Allardyce.
"I was playing for Dunfermline against Falkirk and Big Sam was the youth team coach at Preston and was sent to watch me by the manager John Beck," Moyes recalled.
"I had only been sent off once before in my career and I got sent off for a second time in this game for a deliberate handball.
"I think he went back and said: "What a player I have seen, John!" It is right to say I might not be here had I not gone to Preston. You never know how your career goes.
"That move was a good move for me as far as how my career went and it gave me a springboard. He still reminds me of it, yes!
"Sam's had a brilliant career in management and is one of the senior guys.
"He's experienced, having been to Old Trafford many times, so it will be nothing new to him."