Chelsea`s Carlo Ancelotti, Liverpool`s Roy Hodgson, Aston Villa`s Gerard Houllier and West Ham`s Avram Grant are all reported to be under pressure following a string of disappointing results, while seven Football League managers have lost their job in the last week.

Twenty nine managers have left their posts this season already, 19 by way of dismissal, while 21 coaches have also been sacked as a result.

In an open letter released by the LMA tonight, chief executive Richard Bevan has urged clubs to stop making managers "scapegoats".

He said: "The figures actually serve to highlight the continued chronic short-termism in football manager employment.

"Statistical evidence suggests that the gains from changing football managers are marginal, if indeed there are any at all, and without doubt the sacking of managers is a costly business to football clubs.

"Bridgewater (2010) suggests the short-term "honeymoon" effect of changing manager has historically brought an average 2.5 points for Premier League clubs, a benefit quickly lost as a team's performance dips back some 12 games after the change to a level below that achieved before the change.

"In recent seasons and recent weeks, a number of managers have been dismissed for losing a handful of games in what might well be short-term blips within the normal range, rather than the sustained downturn seen in the past before a managerial change.

"It is clearly the decision of club chairmen whom they hire and fire and when they choose to do this, but the statistics show that a club is likely to end up worse off when they sack their manager, they have less points and are often significantly out of pocket due to monies spent on compensation and paying up contracts.

"Clubs in lower leagues simply cannot afford to keep sacking managers. Short-termism does not work. It is hugely destabilising to the club and its staff and a new manager wishing to stamp his own mark on the playing squad brings with him the additional cost of the transfer budget needed to do so."

"In football, there is an incomprehensible belief that the continued sacrificing of the football manager, the "scapegoat" and installing another will turn around a football club's performance.

"The League Managers Association will continue to protect the interests of its members when they are sacked, by ensuring that clubs agree to appropriate compensation and pay the remainder of outstanding contracts. However we will also continue to clearly state the case against the short-term 'hiring and firing' culture that is endemic in our game."

Such has been the pressure on the four Premier League managers in question that bookmakers have started running special bets on them all being dismissed before the Premier League schedule resumes next weekend.

But rather than managers living in fear of the sack, Bevan would like to see clubs adopt a more long-term vision, look to adopt standard workplace guidelines when dealing with their staff and only part company with their boss if the on-field situation becomes untenable.

He added: "No one is saying that a club should never change manager. The football context changes over time, the circumstances of individual football clubs alter, the goals of employer and employee may no longer match.

"In this unfortunate circumstance, it would seem most sensible for both sides if lessons were adopted from the broader field of human resources to handle this type of situation. Football managers might, for example, like any other type of manager, have regular appraisals.

"In these, the strengths and weaknesses of how the football side of the club is performing might be assessed against realistic expectations and previously, mutually agreed goals. Should the performance of a manager not match up to the agreed goals, or be judged unsatisfactory on appraisal, then a due process of verbal, followed by a written warning is the correct procedure, before ever reaching the final step of dismissal.

"When does this happen? How often does a manager have no warning of what is about to happen? How often does he discover news of his dismissal from the media, from his worried family who have heard the reports? How often when calling the club to check the truth of such accounts has a manager been told that this is not true, only to discover soon after that he has indeed been dismissed?

"This is no way to treat any employee, let alone those whose lives are inextricably bound up in the clubs and game they love.

"We must also look to safeguard the future of football management. It is well documented that the average tenure of dismissed football managers across the four leagues has declined (from three and a half years in 1992 to one year and four months last season).

"Using the average figure, however, masks some frightening figures at the lower end of the scale. The most common period of time for which a first-time manager is in post is between six months and a year.

"Almost half of all first-time managers do not ever get another football manager role, so this may be the total time they have to prove themselves. Currently, 33 league managers, including 10 in the npower Championship have been in charge for less than one year."