He leaves Anfield having scored 54 goals in 202 games since his move from Inter Milan in 2013 and having developed into one of the finest playmakers in European football.
The timing of the £142 million British record transfer has been questioned, however it's been clear that Coutinho has had his heart set on playing for Barca for a very long time.
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In his statement on Coutinho's departure, Jurgen Klopp said: "Philippe was insistent with me, the owners and even his teammates this was a move he was desperate to make happen."
The German coach mentioned "teammates", and it's now been revealed exactly when Coutinho informed his colleagues of his desire to leave Liverpool.
Coutinho's summer saga
To say last summer was a saga is an understatement, from Coutinho handing in a transfer request via email after multiple rejected bids to picking up a suspicious back injury.
Per The Independent, it was in August, during the last transfer window, where the 25-year-old informed Liverpool's players of his intention to leave the club for Barcelona.
When Coutinho told teammates he wanted to leave
The report states that as Klopp's men were preparing for a training session at Melwood, Coutinho walked into the changing room "with an expression attached to his face".
The Brazil international's look was such that he probably didn't need to explain his thoughts, but he did so anyway, in front of the entire squad.
Whether he did so in confidence or out of desperation, it resulted in the club and Fenway Sports Group reinforcing their position not to sell, but Coutinho got his wish in the end.
Life after Coutinho?
Liverpool haven't just lost Coutinho's technical qualities, but also his versatility, seeing as he can operate as a central attacking midfielder as well as off the left-wing.
The main front three of Mohamed Salah, Roberto Firmino and Sadio Mane should continue to fire, but one of the team's attacking midfielders will now have to step up.
Whether it's Adam Lallana, Alex Oxlade-Chamberlain or Naby Keita in the summer, Liverpool must find a way to replace Coutinho's goals, assists and creativity.
As for Barcelona, they could be about to form a potentially unstoppable front four of Coutinho, Lionel Messi, the returning Ousmane Dembele and ex-Liverpool star Luis Suarez.
What do YOU think about how Coutinho told Liverpool's players he wanted to leave? How big a loss is he? Do YOU think he will succeed at Barca? Leave YOUR opinions in the comments box below!News Now - Sport News