Real Madrid fullback Alvaro Arbeloa admits teammate Cristiano Ronaldo finds Anfield intimidating.
Liverpool host Real in the Champions League tonight.
"Even Cristiano has mentioned this is the most difficult away ground from his time in the Premier League," said former Reds fullback Arbeloa.
"It is tough to explain what it is like here. You have to experience it yourself. These big nights in the Champions League are special occasions and it is a special sound. It is a once in a lifetime experience - a special environment you must experience once in your career. But you have to put that to one side because it is an important game.
"It is not a case of warning my team-mates but I have told them of the tremendous atmosphere. The supporters here will drive them forward. It is a special game for Liverpool because they have been five years out of the Champions League. They will put us under pressure.
"The Anfield atmosphere will be working against us. Even if Liverpool had lost 10-0 to QPR I would come here worried because it is a totally different game to the weekend and I know what they are capable of a European night."
