The Brazilian struggled during his time with the La Liga champions but will be hoping to return to the form he produced at Liverpool that made him such a revered talent.
The European transfer window wont shut until 2 September, leaving room for more signings, but Bayern have more than likely concluded their business.
Following the Coutinho announcement, heres how manager Niko Kovac should line up the reigning Bundesliga champions to help them challenge Europes elite.
Goalkeepers & Defenders
Manuel Neuer (GK) - Once regarded as the best keeper in the world, the Bayern captains stock has fallen massively due to his injuries and a poor last campaign. The German looked to be back close to his best though in pre-season though, and will be hoping to carry that through. At 33, its not too late.
Joshua Kimmich (RB) - Probably one of the best attacking full backs in the world, Kimmich has become an assist machine - racking up an astonishing 14 last season, three behind Bundesliga leader Jadon Sancho. His crossing and set-piece delivery have taken his quality up another level of late. Remember when Bayern would never replace Philipp Lahm?
Niklas Süle (CB) - Currently the best centre back at the club. He beat out both Jerome Boateng and Mats Hummels to become an regular starter over the course of last season, and has become one of the most underrated defenders in world football. A blend of deceptive speed, huge stature and progressive passing make him one of the first names on Niko Kovacs team sheet.
Lucas Hernandez (CB) - Despite not being at full fitness yet, the French World Cup winner should start ahead Boateng and fellow Frenchman Benjamin Pavard once he recovers completely from a long-term knee injury. Lucas has vast Champions League experience from his time at Atlético and is a similar type of player to Süle. Oh, and hes a great left back too.
David Alaba (LB) - Alaba is still one of the best in the world at his position, but his performances have been on the wane a little. The Austrian still has the skillset of a complete left back and remains a great set-piece taker - and having just turned 27 this summer, he has plenty of time to return to the top of his game.
Thiago (CM) - The most technically gifted player in the Bayern squad. With Thiago best deployed as a number eight, the Spaniard should take his place in a double pivot as one of the most complete midfielders in the world.
Corentin Tolisso (CM) - The Frenchman gets the nod ahead of new boy Cuissance, Leon Goretzka, Renato Sanches and Javi Martinez. A much more physical number eight than Thiago, Tolisso is a great box-to-box midfielder and has the potential to become one of the best midfielders in the world. Having just returned from a devastating injury, Goretzka could feature more prominently but in crucial games, Tolisso offers much more to the Bayern side on a defensive end.
Serge Gnabry (RM) - Bayerns player of the year last campaign, Gnabry shocked everyone with his great goalscoring threat and efficient dribbling. The 24-year-olds form was a pleasant surprise and he plays superbly alongside striker Robert Lewandowski. Gnabry has a great eye for goal, which Bayern severely lack, and has the quality to change the momentum of a game.
Philippe Coutinho (CAM) - The addition of the 27-year-old is the star power Bayern needed to help challenge for the Champions League this season. He was unable to prove the quality he possesses in a floundering Valverde system at Barcelona and will be hoping he can bring his attacking flair and sensational long-shot quality to Die Roten. Having lost James Rodriguez, Bayern have made a somewhat like for like replacement with the Brazilian able to both create and score in crucial moments.
Kingsley Coman (LM) - Coman will likely start ahead of another loan signing in Ivan Perisic despite Kovacs fondness of his fellow Croatian. The Frenchman has an incredible record of winning a league title in every season hes played in and his dazzling quick feet and lightning pace have often played a role in those campaigns. If the 23-year-old were to add some quality finishing, Bayern would have a front four that would be hard to beat.
Robert Lewandowski (ST) - Its fitting that the Pole gets his own section as he has been in a league of his own for the past couple of years. He has been the Bundesligas top scorer four out of the last six campaigns and doesnt show sign of slowing down anytime soon. A complete striker and capable of playing any role required by the manager, the finishing machine has been a crucial cog to Bayerns success over the years. The only thing missing is that he has yet to show up in crucial Champions League games in a Bayern shirt - probably due to Bayerns recent inability to keep up with Europes elite.