Liverpool boss Rafael Benitez admitted his under-strength side had paid for a series of mistakes in the Champions League defeat at Galatasaray.
Benitez admitted it was difficult for Liverpool to mount a comeback
They lost 3-2 in Istanbul, but had already finished top of Group C.
Benitez said: "We paid for bad mistakes - you cannot expect to win if you make mistakes like that at this level.
"I always felt it was going to be a difficult game for the players. They knew they were already group winners and the job had been done."
It was not a glorious return for Liverpool to the scene of their Champions League triumph against AC Milan in 2005.
He said: "It was more difficult to stage a comeback in such circumstances, as you would in a cup final."
Liverpool left Steven Gerrard, Jose Reina, Steve Finnan and Sami Hyypia at home - fielding a side of youngsters and experienced squad players.
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Benitez said: "I wanted to see my players doing well but also to realise that there are younger team-mates who are waiting for their chance.
"I have rested some senior players, because we have such a busy next couple of months with lots of games. I wanted to see what futures there are for the young players and to be able to plan for that future."
Galatasaray coach Erik Gerets believes Liverpool, with their full team, can flourish in the knockout stages.
He said: "It was a difficult game for Liverpool. They had already done the job they set out to do, before even coming to Istanbul.
"They are a very good team. It is difficult to judge whether they can go all the way - but with their best players, they can win the tournament."