The 25-year-old playmaker completed a £142m move to La Liga giants Barcelona at the weekend to call time on his five-season spell at Anfield.
Coutinho had forged a destructive partnership with Firmino on the pitch, while the two Brazilians were close friends off the pitch following the Liverpool No11’s move to Anfield in 2015.
The former Hoffenheim forward saw another member of his Brazilian clique leave in the summer after Lucas Leiva left Liverpool FC to move to Serie A giants Lazio following nine seasons.
Firmino has produced his best season at Anfield to date following an incredible return of 16 goals in 27 games in all competitions in the 2017-18 campaign.
The South American star took to Instagram to post a heartfelt message for Coutinho that could worry Liverpool FC fans about his happiness at Anfield without his close pal.
Firmino wrote on the photo-sharing app: “Liverpool is no longer the same without you my magical brother.
“I wish you infinite success, that you enjoy life and realise all your dreams brother.
“God is always protecting you and your whole family. It was an honour to play with a magician like you.”
Liverpool FC will welcome Premier League leaders Manchester City to Anfield in their next Premier League game on Sunday afternoon.
The Reds haven’t won the Premier League title but finished in second place in 2002, 2009 and 2014.
The Merseyside outfit will take on Portuguese side FC Porto in their Champions League last-16 clash next month.
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