The two sides meet in the first leg of their Europa League quarter final on Thursday.
The Reds travel to Germany on Thursday for the first leg of their Europa League quarterfinal clash.
They will be wary of the Bundesliga side having seen them dismantle Premier League title contenders Tottenham Hotspur in the last round.
Jurgen Klopp’s side will need their best players on fine form for the game, with the pressure firmly on the forward players to score the crucial away goals they will need.
And in that regard Thompson is hoping Roberto Firmino is fit for the game, believing the Brazilian is the side’s most important player.
"I'm hoping Firmino will be fit as he's probably the most important player with the form he's been in," he told Sky Sports.
"It's the toughest game they could have got but if we go through then they've got a really good chance of winning the competition."
While Thompson has focused on Liverpool’s forward players, it will surely be the defence that will be crucial to their hopes.
They must find a way of containing Pierre-Emerick Aubameyang, who has been in sensational form for Thomas Tuchel’s side this season.
He currently sits on 37 goals in all competitions so far, seven of which have came in his seven Europa League games, meaning Mamadou Sakho and co face a tough evening on Thursday.