Manchester United manager Sir Alex Ferguson is determined not to become paranoid about the decisions which have gone against his team in their recent clashes with Chelsea.
The teams will meet in the Champions League quarter-finals next month, and also have a Barclays Premier League match at Old Trafford in May, which could have an impact on the title race.
Ferguson was given a five-match touchline ban and a £30,000 fine by the Football Association following his verbal attack on referee Martin Atkinson at Stamford Bridge in February, but told ESPN Press Pass: "I think the last few games we've had terrible decisions against us and you've just got to be careful you don't have paranoia about it."
He added: "But ability-wise we're a good team, we played exceptionally well at Chelsea in the last game. We were very, very unlucky and we didn't deserve to lose the game."
United travel to London to face Carlo Ancelotti's side next Wednesday in the first leg of the quarter-final, with memories of that performance at Stamford Bridge last time providing Ferguson with encouragement.
He said: "We take that into the game because ability-wise we don't have a problem."
Ferguson says he understands why referees are protected by the game's authorities, but believes there should be a right to freely discuss performances of officials, providing any criticism is justifiable.
"If you speak your mind it's a problem in the game," Ferguson said.
"They're very strong in supporting the referees.
"In a way I totally agree with that, but there's got to be fair comment also, and I think I try to do that."
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