UEFA have appointed ref Frank de Bleeckere for the second-leg of Real Madrid's Champions League semi at Barcelona.
Mourinho was enraged by the dismissal of makeshift midfielder Pepe by Wolfgang Stark and afterwards read out a list of officials he believes have made decisions which have benefited Barca in previous years.
De Bleeckere was on that list after opting to send off Thiago Motta in last season's last-four clash between Inter, then managed by Mourinho, and Barca.
"I can't say what I feel. I only leave one question. Why?" said Mourinho on Wednesday.
"Why? Ovrebo, Bussaca, Frisk, Stark, De Bleeckere. Why to all these people. Each semi-final always brings the same.
"We're talking about a fantastic football team. So why?"
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