Saturday’s 3-1 loss at home to arch-rivals Rangers sparked protests outside Celtic Park and was the final straw for club bosses.
“Celtic Football Club today announces that it has decided to terminate the contract of manager Wilfried Nancy with immediate effect,” said a club statement.
The Hoops added that the Frenchman’s coaching staff and Paul Tisdale, the head of football operations, had also left the club.
Nancy, previously in charge at MLS side Columbus Crew, started his job as Celtic manager on December 4, signing a two-and-a-half-year contract and taking over from interim boss Martin O’Neill.
He promised to give the fans “a strong, exciting, attacking, winning football team they can be so proud of”.
But the appointment quickly turned into a nightmare, with four defeats in his first four games, including a 3-1 defeat to St Mirren in the Scottish League Cup final.
It was the first time Celtic had lost four games in a row since a similar run under celebrated manager Jock Stein in 1978.
Nancy finally earned his first wins in late December, with Celtic beating Aberdeen and then Livingston.
But they lost to Motherwell and collapsed to a 3-1 defeat at home to Rangers at the weekend, despite taking the lead at Celtic Park.
That defeat left Celtic second in the table, six points behind Scottish Premiership leaders Hearts.
The Glasgow club won seven of their eight games under caretaker boss O’Neill, who took charge following the departure in October of Brendan Rogers, who is now in charge at Saudi Pro League side Al-Qadsiah.
Former Celtic striker Chris Sutton compared Nancy’s position to that of Ruben Amorim, sacked as manager of struggling English giants Manchester United just hours earlier.
“It’s a bit like the Ruben Amorim situation at Manchester United but over a shorter period,” Sutton told Sky Sports.
“He was fixated on changing Celtic’s style, moving to a 3-4-3, playing one particular way. He just wasn’t adaptable and for Celtic to lose six and [give up] as many goals as they did. It was kamikaze stuff from Nancy.
“You want to give a manager time, but I think Celtic have acted decisively because there is a league title to win.”
Celtic and Rangers form Scotland’s “Old Firm”, with both clubs crowned Scottish champions 55 times.
Celtic, the first British team to lift the European Cup, in 1967, have won 13 of the past 14 league titles. (AFP)
