The Brazil international returned to Germany for the first time since his summer move to Liverpool from Hoffenheim on Wednesday afternoon.
Firmino trained with the rest of his team-mates as Jurgen Klopp prepared his side for the first leg of their last-32 clash against Augsburg.
The South American has been in excellent form in 2016 after scoring five goals and making three assists in the Premier League.
However, Firmino appeared in a serious mood as he posted a selfie from the comfort of his hotel room ahead of Thursday’s game against Augsburg.
Firmino joined Liverpool in a £29m deal from Bundesliga side Hoffenheim last summer, becoming the third most-expensive signing in the club’s history.
Liverpool are unbeaten in this season’s Europa League after two victories and four draws in the group stage.
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