Fans of Swedish side Malmo, who are playing in the Champions League this season, were extremely upset with the decision to send defender Erik Johansson off for dissent in the closing stages of Wednesday night's 2-0 defeat to Juventus.
More than 20,000 supporters began to chant the words "UEFA Mafia" towards referee Pedro Proença after the Portuguese official gave several decisions in favour of Serie A giants Juve.
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"The crowd was angry. UEFA talk so much about respect, but I do not feel we got the respect of the referee today. I think he had a bad day", said Malmo coach Åge Hareide.
Indeed, the crowd was so angry that Proença and his fellow officials needed to be accompanied off the pitch by security staff, one of whom grabbed the referee to get him to leave the pitch quicker.
Malmo need to win their last Champions League group stage match against Greek outfit Olympiakos if they are to stand a chance of qualifying for the Europa League.
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