Grimsby Town have announced that manager Graham Rodger has been "relieved of his current duties" after five months in charge.
The Mariners, who are without a win in six games, have slipped to 22nd place in League Two - having been beaten finalists in last season's play-offs.
Assistant boss Stuart Watkiss will take over as caretaker boss.
"He has been a loyal servant to the club, but has become a victim of circumstances," a club statement read.
"Unfortunately, injuries to Michael Reddy, Gary Cohen, Isaiah Rankin and recent signing Kevin James have made Graham's job especially difficult.
The shame of it is that this man deserved better
Grimsby Town club statement
"Such is the pressure on this results-based industry that the board has arrived at one of its most difficult decision.
"Graham has qualities this club needs - the shame of it is that this man deserved better."
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Rodger, 39, became manager in June after ex-boss Russell Slade left Blundell Park.
He made 134 league appearances for Grimsby as a player, before spending time on the coaching staff under former bosses Paul Groves, Nicky Law and Slade.
Meanwhile, Watkiss remained tight-lipped when asked if he would be applying to succeed Rodger.
"I've been asked to take over first-team affairs and that's all I'm thinking about at the moment," Watkiss said.
"It's a very sad for the club with Graham leaving because he was such an outstanding servant to Grimsby Town."