The FA have charged Manchester United boss Sir Alex Ferguson with improper conduct over comments he made about referee Howard Webb.Ferguson made the comments in the lead-up to his side's 2-1 English Premier League win over Chelsea at Old Trafford on May 8, when Ferguson said he feared 'getting a bad decision'.

Ferguson made the remark after praising Webb's abilities, but he broke an FA rule that states managers should not talk about referees prior to a match.

"We are getting the best referee, there is no doubt about that," he said before the Chelsea game.

"But (getting a bad decision) is definitely our big fear."

"We have the players to do it all right. We just hope it's our turn for a little bit of luck."

The 69-year-old Scotsman has until 4pm on May 16 to respond to the charge, and he has only recently returned to the touchline after being banned for five games after criticism of referee Martin Atkinson, who officiated United's 2-1 loss to Chelsea in March.