Wigan have sacked boss Chris Hutchings following the club's slump into the bottom three of the Premier League.
Hutchings was sacked two days after losing to Chelsea
Assistant manager Frank Barlow takes charge on a caretaker basis, starting with Sunday's trip to Tottenham.
Chairman Dave Whelan said: "It is crucial for our development that we maintain our Premier League status.
"Following results and performances in recent matches we feel it is critical to act now. It is in the best interests of the club and its long-term future."
Hutchings was appointed in May following the resignation of Paul Jewell, stepping up from his role as assistant manager.
He had been Jewell's deputy for the six-year stretch in which the team had gone from the obscurity of League One to take their place among English football's elite.
Hutchings said he was immensely proud of his achievements at Wigan and was sad to leave the club.
"When I was given the opportunity to manage this club I had no hesitation in taking on the challenge," he said.
"I believe I have assembled an excellent bunch of players, a superb squad of professionals, and I still firmly believe that over time they will prove their worth and push this club to the next level.
"My only regret is that I will not be here to see that progression reach its summit."
Hutchings, 50, had also succeeded Jewell at Bradford City in 2000, but lasted less than five months after winning one of 12 Premiership games.
This season in the Premier League, Wigan have collected just eight points from 12 matches to be in the relegation zone.
Athletic were beaten 2-0 at home by Chelsea on Saturday.
It was their sixth defeat in succession, with their last league victory coming against Sunderland at the JJB Stadium on 18 August.
However, League Managers' Association vice-chairman Frank Clark feels Hutchings should have been given more time to turn results around.
"Chris will be bitterly disappointed, and I'm disappointed for him that it's been done so quickly," said Clark.
"I think managers are being dismissed too hastily and it breeds instability in the game - it doesn't do the game any good at all."
Former Liverpool defender Alan Hansen believes Whelan had to take such measures in the best interests of the football club.
"Hutchings is unlucky but, from chairman Whelan's point of view, it is good to change things early," he told BBC Sport.
"In a nutshell, dropping out of the Premier League would be a disaster for them."
Whelan added: "This has been a very difficult decision for me and the board to make.
I will not be commenting on any names or speculation until I have found [a replacement]
"Having been so close to the team and such a big part of our success, I felt Chris deserved to be given the chance to take over as number one last summer.
"He has worked very hard since becoming manager and I cannot fault his effort and commitment to the cause."
He said his energies would now be "fully focused" on selecting a new coach.
Whelan added: "This search will be exhaustive and I will not be commenting on any names or speculation until I have found the man."
Jewell, who had announced his intention to take a break from football following his resignation in May, has since been linked with the jobs at Leicester City and Bolton Wanderers.
Hutchings is the fourth Premier League manager to part company with his club this season following the departures of Martin Jol (Tottenham), Sammy Lee (Bolton) and Jose Mourinho (Chelsea).