Faison stars in the TV Land comedy as Phil Chase, a womanising sports agent. His former co-star Braff will play a guest role in a season two episode, TVLine reports.
The pair previously played best friends JD (Braff) and Turk (Faison) on medical comedy Scrubs between 2001 and 2010.
Braff's Exes stint will see him cast as Chuck Feeney, a pro tennis player who becomes Phil's client, but may have romantic feelings for his new agent.
Glee actress Dot-Marie Jones will also appear in an episode of The Exes season two, starring in the August 22 episode.
Braff's appearance will air the following week, on August 29 at 10.30/9.30c on TV Land.
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Watch the cast of The Exes talk about season two below: