Carlo Ancelotti admitted he blundered by playing Fernando Torres after Chelsea were knocked out of the Champions League by Manchester United.
He also insisted the decision about whether he keeps his job at Stamford Bridge after his team failed once more to deliver the Holy Grail of Europe's top club trophy to watching owner Roman Abramovich was out of his hands.
Ancelotti gambled by starting £50million striker Torres and leaving Didier Drogba on the bench, even though Torres had not scored in 817 minutes and 13 matches for club and country.
Torres suffered a torrid first 45 minutes and was replaced at half-time by Drogba, who scored in the second half.
When asked if it had been a mistake to start with Torres, Ancelotti said: "Maybe. Could be. I told you a lot of times this season I wanted to start with Fernando for this kind of game, these type of tactics.
"Didier played well in the second half. I wanted to put more pressure up front because we needed to score. Didier was fresh and he could use his power up front. This was the reason I took out Fernando."
United boss Sir Alex Ferguson, however, was in no doubt that it was the huge fee Chelsea splashed out for Torres in January which forced Ancelotti's hand.
Ferguson said: "A lot of people thought Drogba would play. I thought having signed Torres for the money they did they had to play him. I wasn't 100% sure but I couldn't see how they could leave Torres out."
Ferguson, however, insisted he was not criticising Chelsea for signing Torres.
"They had the opportunity to sign Torres and I don't think anyone would have turned it down," Ferguson said. "Everyone said at the time it was fantastic business.
"You can't criticise him (Ancelotti) for that, it was a good signing. It isn't working at the moment but he is a young man and there are other seasons ahead."
Two goals from Javier Hernandez and Park Ji-sung gave Manchester United a 2-1 victory on the night and a comfortable 3-1 aggregate triumph over a Chelsea side who finished with 10 men after Ramires was sent off for a second bookable offence.
On his own future Ancelotti said: "I'm not concerned. I have to work and try to do my best, It is not my decision to stay or not to stay here."