Sir Alex Ferguson believes that managers should be free from the constant criticism that he believes they receive and be protected from it like referees.

The Manchester United boss has been stunned by the number of sackings this season in the Premier League and the increase in pressure from media and fans alike.

With the Red Devils due to entertain Liverpool on Sunday, Ferguson was also unhappy with situations like the one that Rafa Benitez faced when it was revealed the club's owners had approached Jorgen Klinsmann.

"I don't think it helps. I don't think any media attention helps when the manager is being criticised," Ferguson said.

"There is talk of criticism of referees but no-one gets criticised more than managers - the humiliation managers endure every season," he told reporters.

"The rapidity of managers being sacked this season is at an all-time peak, particularly in the premier division.

"Every Christmas time there are a third of managers in the country wondering about their jobs and going home to tell their kids they haven't got a job.

"That's the humiliation managers face every time."