Barcelona had a player sent off in both legs of their Champions League quarter-final against Atletico Madrid
Barcelona say refereeing "errors" cost them a place in the semi-finals of the Champions League, and have caused "significant sporting and financial harm to the club".
As a result, the Spanish giants have made a second complaint to Uefa about officiating across both legs of the tie.
Barca had a player sent off in each leg of their 3-2 aggregate defeat by Spanish rivals Atletico Madrid, with their 2-1 win on Tuesday not enough to overturn a 2-0 deficit from the first game.
In both cases, a yellow card was upgraded to a red after the referee was instructed to review at a pitchside monitor the possible denial of a goalscoring opportunity.
