Derek McInnes admitted Aberdeen finished second to Rijeka – although referee Harald Lechner was blamed for having hit the last nail in the Europa League coffin.
The Dons lost two goals from their own offensive playoffs, and in between Funjo Ojo was sent off in a crazy 32-minute opening at Pittodrie.
This ended the duel and the Croats achieved an impressive 4-0 aggregate victory – although McInnes was dismayed that Ojo had been dropped off for Aberdeen.
He said, "I do not think Funso is naive, he got caught on the ball and challenged him.
"The second one might be more of a yellow card than the first one, but I'm still shaking my head.
"The referee hammered the last nail into the coffin by sending it away.
"I'm not blaming the referee, I have to stress that – but God, he had a big role tonight.
"After submitting it is unfair for my players to be criticized, the game was done effectively.
"It was a terrible decision to make these two yellow cards punishable. "I've never seen anything like it.
"There were other challenges he did not think were yellow cards, which surprised me, considering what he did to Funso.
"There were Rijeka players with four or five fouls who were not booked.
"It's a bad decision from us – and a terrible decision by the referee turned it into a very disappointing night.
"You are not in this situation very often, a goal that was reached so early by up to ten men, when your fans are ready for a big yes and get involved."
McInnes was annoyed that his team lost both goals from their own attacking positions.
He admitted: "We have made some really bad decisions from the very first minute.
"The first goal comes from our corner, a bad performance, and in the second phase we get hit on the bar.
"Losing the first goal was like jumping in a balloon because the fans showed up and played their part."
McInnes also admitted that he had tried to cheat Rijeka coach Igor Biscan by saying that Sam Cosgrove was injured.
He confirmed: "He was fit. I was not completely honest because we had not completely excluded him. I apologize to you guys for that.
"I did not want them to know he was there until they saw the team hand.
"We wanted to see if Sam reacted today, he wanted to try it.
"He was fit, but we dismissed him after about 50 minutes, so we do not take more risks for Sunday."
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