Assistant manager John Kennedy is favourite to take the reins at Celtic for the remainder of the season after Neil Lennon stepped down on Wednesday.
Lennon has called time on his second stint as boss, with the club sitting 18 points behind rivals Rangers and set to miss out on a 10th-straight league title.
They have failed to win 11 of their 30 Scottish Premiership matches this season and fell to defeat at bottom club Ross County on Sunday.
A statement from defending champions said: “Celtic Football Club today announced that Neil Lennon has resigned from his position as Football Manager with immediate effect.
“We thank Neil sincerely for all he has done for the club and we wish him every success going forward.”
Kennedy has been installed as the early favourite and would likely take the role on an interim basis, with Eddie Howe and Frank Lampard among the contenders having both left Premier League jobs over the course of the last year.
Scotland manager Steve Clarke is also in the reckoning for the Parkhead gig, though it remains to be seen how he would juggle preparation for the fortcoming European Championships were he to take the job ahead of the summer.
Rafael Benitez, who left as coach of Chinese Super League side Dalian Pro in January, is in to 9/1 for the Celtic job as he considers his next move in management.
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