After losing five of his first seven games in charge, it was this weekend’s loss against Rangers which sealed the fate of Nancy, who has failed to make an impact with the Scottish side who trail league leaders Hearts by five points.
The 48-year-old signed a two-and-a-half-year contract with the Scottish champions after leaving Columbus Crew and became the first Celtic manager to lose his first two games in charge in a statistic which summed up his time with the club.
The club announced the decision on Monday, hours after Manchester United sacked Ruben Amorim in the morning.
“Celtic Football Club today announces that it has decided to terminate the contract of manager Wilfried Nancy, with immediate effect.
“The Club thanks Wilfried for his efforts and wishes him and his family well for the future.
“A further update will be provided to supporters as soon as is practical.”
Nancy insisted that "things will work out" for him and his side after the Rangers result, but the board did not seem to agree as they now search for a new manager.
Having won seven of their eight games under interim manager Martin O'Neill, the former Celtic boss may step in once more in a permanent deal as the side aim to revive their title chances.
Celtic said Nancy’s assistants Kwame Ampadu, Jules Gueguen and Maxime Chalier and the head of football operations, Paul Tisdale, had also left.