ANDY Wilkinson's red card appeal was rejected because the Football Association could not determine that referee Darren Deadman had made a "blatant mistake".
Boss Ian Holloway is adamant that the right back's challenge on Blackburn's Ben Marshall deserved no more than a booking.
But the FA yesterday rejected Millwall's protests and Wilkinson will now serve a three-match ban.
Holloway, who was sent to the stands during Tuesday's 2-2 draw, has been warned about his future conduct by Wembley chiefs.
"It was no more than a yellow card in my opinion but they can't prove that it was a blatant mistake by the referee," Holloway said on Friday.
"It has to be crystal clear apparently.
"The whole system needs refreshing and looking at, from top to bottom. We can all see the replays and see that they are wrong, but they're not admitting it.
"I got sent off for appealing about a decision too many times. Well, get your decisions right, be consistent and then I won't have to complain!
"But when a free kick is given against us, we've got to head it out. That's the flipside."
Both of Blackburn's goals came from set-pieces, meaning the Lions have now conceded eight times in a row from free kicks or corners.
"I'm going to have Sid Nelson, Alfie Pavey and Jake Goodman steaming in on headers this morning and hopefully some of my lads will head it out," Holloway added.
"If they don't, they'll stay at the training ground until it's dark. That's all we've got to sort out because otherwise we're playing fantastically well."