David Moyes will become only the fifth former Manchester United boss in the post-War era to face the Reds when Sunderland provide the opposition on Boxing Day.
To mark the occasion, we have researched the records of the previous four men who've managed United and later been in the opposing dugout, as Moyes prepares for his first match at Old Trafford since leaving the club in April 2014.
WILF McGUINNESS
The former United player and coach who had the uneviable task of succeeding Sir Matt Busby as manager brought his York City side to Old Trafford for a league game in March 1975, five years after his 18-month reign as Reds boss ended abruptly.