Blige was cast in the movie adaptation of Cynthia Mort's Nina in 2010 and was due to begin filming last year (Oct11).
However, the project suffered a funding setback which delayed the start of the shoot indefinitely, and the problems prompted Blige to step down from the role.
Producers have since resolved the investment issue and Saldana has signed up in the singer's place, days after news of the Avatar beauty's involvement in a new Simone biopic surfaced earlier this week (begs14Aug12).
She will lead the cast when cameras finally begin to roll in Los Angeles this October (12), according to The Hollywood Reporter.
Nina, which focuses on the jazz icon's relationship with her manager Clifton Henderson, will co-star David Oyelowo.