The five-time winners could easily have finished the match three or four goals in arrears after a hammering from Standard Liege in everything but goals.

Liverpool chief Benitez said: "We were not surprised by the fine performance of the Liege side, we had seen enough of them to know they were a good, aggressive side.

"The real surprise for me was the way Liverpool played. The only positive to take from the match was the fact that we did not concede a goal.

"We will have to be a lot better in the second leg at Anfield, much better.

"We have been playing well in pre-season, looking confident and passing the ball well.

"But we did not do any of those things. I did not want to bring Steven Gerrard on because the doctors had told me he was not fit enough to start the match.

"We waited until well into the second-half before using him, but we were not controlling the game and I had to bring him on."

Gerrard was initially ruled out with a thigh strain and looked well short of his combative best when he eventually entered the fray.

Benitez added: "This game was far more difficult than we expected. And Jose Reina was the man of the match."

Reina saved a first-half penalty and also looked to have clawed one effort back from behind the line early on.

Benitez said: "We know we can always rely on Pepe to stop penalties, but we have been told that the other effort may have been behind the line, but these things happen."

Liege coach Laszlo Boloni praised his own side's performance, but said: "Liverpool maybe came here asleep and not expecting this sort of game.

"Maybe, though, we have woken them up for the second-leg, which will me much harder for us.

"We felt that if we did not lose this first-leg, we would still be in with a chance. We know, though, that we still have to score and that could be the problem.

"But I want to praise my team. They attacked Liverpool from the start, and when their goalkeeper pulled the ball back from behind the line, maybe the referee was asleep too."