Celtic have sacked Wilfried Nancy after one month in charge with Martin O'Neill returning as manager until the end of the 2025/26 season.
Frenchman Nancy, who was recruited from MLS side Columbus Crew on December 3, oversaw six defeats in his eight matches in charge in all competitions.
Nancy's time in Glasgow began with four successive losses including league defeats to Hearts and Dundee United alongside losing the Premier Sports Cup final to St. Mirren and a UEFA Europa League clash with AS Roma.
Victories over Aberdeen and Livingston followed but this was followed by a 2-0 defeat against Motherwell and a 3-1 home loss to Rangers in the club's opening game of 2026.
Head of Football Operations, Paul Tisdale has also departed the club alongside Nancy and his coaching team.
Brendan Rodgers quit his position as Celtic boss in October with Martin O'Neill taking temporary charge prior to Nancy's appointment.
Now he will be tasked with challenging William Hill Premiership leaders Hearts with the gap between the teams sitting at six points.
O’Neill told the club's website: “I am really pleased, in fact, very honoured to be asked back to manage the team again and I am looking forward to getting back to work again with the players.
“I know we would all have hoped for things to have worked out differently under Wilfried and I personally want to wish him good luck with everything he does in the game. He is a fine man and I am sure he will go on and achieve success again, I have no doubt of that.
“For me, I've been asked to take this great job on again and my focus will be to try and get us back to winning ways if we can. We will need everyone right behind us.
“We still have a lot to look forward to and a lot to try and achieve, and myself, Shaun and the coaching staff and, of course, the players will be giving everything to achieve all the success we can for the club.”