Marseille boss Erik Gerets has likened Liverpool to Duracell bunnies because they can run forever.

The Belgian, who has twice plotted victories over Liverpool in Europe, first for Galatasaray and then in Marseille’s win at Anfield last season, admits to being concerned about the level of form the five-time European Cup winners achieved in beating the current champions on Saturday.

Gerets sends out his Marseille side, undefeated this term, tomorrow against a side brimming with confidence after their victory over Manchester United.

And Gerets is even more worried that Liverpool beat United without Fernando Torres and with captain Steven Gerrard only involved for 20 minutes.

He said: “If I had been asked five days ago whether I was happy with Liverpool not having their best two players, it would have been a different answer to now.

“I love watching Premier League football played at that pace. I really enjoyed watching Liverpool’s game with Manchester United.

“Liverpool are like the Duracell bunnies - they are an example to the rest of the world for the effort they put in. You just wind them up and off they go.”

He added: “Liverpool have a fantastic coach, a fantastic team. I know that Manchester United have cut their lead of titles (now 18-17 in the Merseysiders’ favour) but I really hope that Liverpool win the Premier League, and somehow we survive in this group and end up playing them in the Champions League final.”

Gerets has bitter experience of facing a fired-up Liverpool, having suffered at their hands 4-0 last December at Stade Velodrome.

He said: “Liverpool do not surprise me any more. They outplayed us then in everything they did, physically and tactically.

“But we will not let it happen again because we aim to cut out those mistakes this time.”