Rafa Benitez accepts Steven Gerrard will find it tough to continue his recent good form when Liverpool host Chelsea on Wednesday night.
The Premier League rivals meet for the fifth year in succession in the Champions League when Chelsea travel to Anfield, and key to Liverpool's hopes is how Gerrard performs.
The England midfielder has been in inspired form over the past month but Benitez is aware he will find it tough to break down a side containing the likes of Michael Essien, Michael Ballack and Frank Lampard.
"It is very difficult to stop Stevie when he is at his best but we have to remember who we are up against," said the Liverpool boss.
"We are facing a team packed with very good players and maybe it will present a different test for Stevie.
"If the likes of Michael Essien, Michael Ballack or Frank Lampard are on top of their game, they will take some stopping.
"We all value Stevie's contribution very highly and the fact that we have signed him up on a long-term contract shows we are doing our job properly.
"But make no mistake, he has got a challenge on his hands against this Chelsea team."
In the previous two-legged knockout clashes between Liverpool and Chelsea, home advantage in the first match has proved a hindrance, with the away side going on to win the overall tie.
Liverpool went out last season after a late John Arne Riise own goal at Anfield in the first leg handed the Blues a crucial away goal and an eventual 4-3 aggregate victory, but Benitez is bullish.
He added: "We will change this. Last year we played very well and made a mistake at the end that made a massive difference."If you play well, score goals and keep a clean sheet, then there is no reason why you cannot go through. I think what has happened before is just a coincidence."