The Premier League side welcome the Bundesliga champions to Anfield on Tuesday night for a Champions League last 16 tie.
Jurgen Klopp was expected to have his frightening front three of Sadio Mane, Mo Salah and Firmino available – but late injury concerns have emerged over the latter.
John Barnes has compared the Brazilian with opposite number Lewandowski, insisting they are different players in different systems.
“Lewandowski is a proper number nine, a proper goal scorer. Firmino is different,” Barnes exclusively told bookmaker comparison platform BonusCodeBets.co.uk.
“He likes to drop short and causes problems for defenders in doing so, allowing Salah and Mané to advance into the box and score goals. You can’t prepare for that.
“Lewandowski is a six-yard box player where Firmino isn’t. When the ball comes into the box from crosses and set pieces, he’s incredibly dangerous and a goal poacher, who is always going to cause teams problems.
“Even though Bayern may not be the team they were, you have to be very careful when the ball gets into the box. Lewandowski for me is the best classic number nine in the world.
“Lewandowski would be similar to playing with John Aldridge, he’d be scoring more, and I’d be supplying. But, for selfish reasons, I’d much rather play with Firmino as he’d make me score more goals.
“If Lewandowski played with Salah and Mané, he’d probably score more goals than Firmino; but then Salah and Mané wouldn’t get as many.”
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