Sam Allardyce, only two years ago a rival of Curbishley's for the England job, last night became the eighth top flight manager to leave his post this season.

Allardyce was given just eight months in charge at Newcastle having ended an eight-year stint at Bolton by guiding the unfashionable Trotters into the UEFA Cup.

Curbishley fears many of the new owners entering the Barclays Premier League do so with business ambitions and are not prepared to sit patiently during a poor run of form.

Allardyce and Derby's Billy Davies were both sacked by new chairmen of their respective clubs, while Rafael Benitez does not have the smoothest relationship with Liverpool's American owners.

Jose Mourinho, Martin Jol, Lawrie Sanchez, Sammy Lee and Chris Hutchings have also left their posts this season and Curbishley believes it is time for a reality check.

"This season it has been quite unprecedented. It is very difficult to get your head around eight managers going in a season, especially when the top four are bombproof," said Curbishley.

"I didn't see it coming and I don't think Sam did after just eight months but at the moment it is market forces.

"Lots of people have come into the game and many chairmen have not been through the experience of having a bad time.

"They are all new to it. Perhaps that is one of the reasons why so many have gone so far this season.

"They don't have the experience of going through a bad time - if you can call mid-table a bad time." Curbishley, who was surprised to hear the news from Newcastle last night, believes the fact Allardyce was hired by the previous regime at St James' Park did not help his cause.

He also feels Newcastle chairman Michael Ashley was swayed by the supporters, many of whom were growing increasingly frustrated with the direct style of football.

Curbishley said: "There was no danger of them going down and a couple of wins would have seen them in the top eight.

"I would have thought there would be more time but with chairmen taking over clubs it is their prerogative.

"The fans probably have the biggest influence on what goes on and the Newcastle chairman was sitting in with them, so it must have been a bit louder."

In many ways, West Ham went through a similar situation last year with Alan Pardew sacked shortly after the Icelandic takeover.

It took Curbishley months to haul West Ham out of their trough, as they went on a 10-game run without a win that took them bottom of the table.

But Curbishley has frequently and publicly recognised the support he received during that period from Eggert Magnusson, who was chairman at the time.

Twelve months ago, Curbishley was frantically buying up players in the January transfer window in the hope it would spark something of a recovery.

With West Ham now mid-table, Curbishley has no pressing plans to do any business this month unless he suffers further bad luck on the injury front.

Scott Parker is out for six weeks with a knee injury but two of West Ham's other big summer signings, Craig Bellamy and Julien Faubert are on the comeback trail.

"If it gets to a critical situation in one area then we are looking at what is available in the transfer window but things are slowly improving," said Curbishley.

"I've got so many players who have been out injured but quite a few are returning. If they return my squad is back to where I want it to be.

"The people who do enter the transfer window at this stage have to. You have seen Derby have a go and it is where we found ourselves last year.

"I would much prefer to have the players who are already here and understand us than bring someone in from outside.

Faubert played a reserve team game on Monday and Bellamy is set to start full training after the weekend.