Over the years, Sir Alex Ferguson has developed a reputation as a touchline firebrand.
Referee Jeff Winter was a particular target. Ferguson was sent off by fourth official Winter at Newcastle in 2003 (pictured) having earlier criticised Winter's "ludicrous" refereeing.
Ferguson also clashed on several occasions with referees' chief Keith Hackett, variously accusing officials of bias in favour of Chelsea, or against his club.
"Hackett has got a lot to answer for in this country," said Ferguson in March this year.
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