The Reds boss was furious after Raheem Sterling had a strike disallowed after he was incorrectly deemed to have been offside, before Luis Suarez was denied a late penalty.
Rodgers said after Liverpool’s defeat at The Etihad: “I never go on about officials but I thought they were horrendous.
“The linesman gave Raheem offside in the first half but they were not even on the same cut of grass. If you are working at this level you have got to get those right.”
In his post-match media conference, the Northern Irishman also questioned the decision to appoint Mason, who hails from Bolton, to referee the Eastlands clash.
“Hopefully we won’t have a Greater Manchester referee with Liverpool-Manchester games in future,” Rodgers added.
“We had nothing that went our way at all.”
Rodgers, whose side are fourth in the Premier League table, accepted the charge on Wednesday, and the FA delivered their judgement earlier today.
A statement read: “Following an Independent Regulatory Commission hearing today, Liverpool manager Brendan Rodgers has been fined £8,000 and warned as to his future conduct after he admitted an FA misconduct charge.
“Rodgers was charged for a breach of FA Rule E3 in that his post-match comments following Liverpool’s game at Manchester City on 26 December 2013 constituted improper conduct in that they called into question the integrity of the match referee, and/or implied that the match referee was motivated by bias; and/or brought the game into disrepute; and/or amounted to a failure to act in the best interests of the game.”
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