Aitor Karanka is favourite to take over at Birmingham after they sacked Harry Redknapp, while Chesterfield and Port Vale also need new managers.
Birmingham parted company with Redknapp after slumping to a 3-1 defeat at home to Preston, one which leaves them 23rd in the Championship table.
It was their sixth loss in succession and sees the end of a tenure which began late last season.
Redknapp came in to save the Blues from relegation and achieved that goal with two wins in three matches, before signing a one-year deal to stay at the club.
Despite signing 14 players during the summer transfer window, Birmingham have managed just one win from six games this time around.
Former Blues midfielder Carsley has been appointed as caretaker-manager, stepping up from his role with the development squad but has now drifted to 7/1 in the betting to replace Redknapp..
Former Middlesbrough boss Aitor Karanka is the new 6/4 favourite with Sky Bet to take the hot-seat from Steve Cotterill, who is into 3/1 (from 6/1 overnight).
"Maybe not this year but over the next two years I would have got promotion," a disappointed Redknapp told the Birmingham Mail.
"I had to do well this year but I would have stayed because I loved it there, absolutely loved my time there.
"I am not an idiot, I am not a silly person who goes around saying things, I think I have been round long enough."
Redknapp was not the only Sky Bet EFL manager to lose his job on Saturday, as Chesterfield dismissed Gary Caldwell and Port Vale parted company with Michael Brown.
The Spireites lost their seventh game of the season and were quick to act, removing the man who had taken over from Danny Wilson in January.
Director and company secretary Ashley Carson told the club's website: "Gary has worked very hard during his time at the club, but we find ourselves in a lowly position after providing him with substantial backing in the transfer market."
Jack Lester is the new 6/1 favourite for the role with Kevin Davies available at 8/1.
EFL basement dwellers Port Vale announced that they and Brown had "mutually agreed" a parting of the ways.
The club's chief executive Colin Garlick said: "We are all very disappointed with the start to the season.
"I know Michael and his staff have worked extremely hard to try and rebuild the club and achieve the results that we were looking for but unfortunately, this has not happened. I would like to thank Michael for his hard work and wish him and his family all the very best for the future."
David Kelly and Chris Morgan ave been placed in temporary charge of a team which sits bottom of League Two having collected just four points from eight games thus far.
Both men were chalked up by Sky Bet at 6/1 to take the job permanently but it was Justin Edinburgh, recently axed by Northampton, installed as favourite at 4/1.
