Besiktas head coach Senol Gunes shouldered the blame for his side's Champions League exit after a 6-0 thrashing at Dynamo Kiev.
The Turkish side would have reached the last 16 with a victory in Ukraine - while a draw could have proved enough depending on Napoli and Benfica's result - but they were stunned by their rampant hosts.
Besiktas finished the game with nine men, having lost Andreas Beck to a controversial red card amid four first-half goals - and Gunes believed he was at fault for his players losing focus.
"We're upset by this result, because we were a team aiming to qualify from the group," he told a post-match news conference. "It's a pity to see one year's work vanish in one night.
"We have suffered a huge defeat, but we got some valuable experience. The result is my fault, but this game is consigned to history already. We have to look at our next aims.
"After conceding first, our players lost concentration and looked defeated. I think in that situation you have to stay calm and focused."
Dynamo Kiev coach Serhiy Rebrov, meanwhile, insisted Besiktas did not deserve such a humbling score-line, although he agreed with Beck's dismissal.
"Besiktas did not deserve to lose like that," he said. "But it was a red card. I did not see that injustice - I do not think [referee Craig Thomson] was doing an injustice."
