The project will star Liev Schreiber as Donovan, a professional 'fixer' who solves problems for LA's rich and famous.
Scarface actor Bauer will play Avi, Ray's ally at his detective agency, according to Deadline.
His past credits include a recent recurring role on AMC's Breaking Bad and such films as 1996's Primal Fear and 2000's Traffic.
Newcomer Devon Bagby has also been cast as Ray's son Conor in the Ray Donovan pilot. Other stars attached include Eddie Marsan (Sherlock Holmes), Dash Mihok (I Am Legend) and Paula Malcomson (The Hunger Games).
Jon Voight, Elliott Gould, The L Word's Kate Moennig and House star Peter Jacobson will also appear in the drama, created by Southland's Ann Biderman.
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