Jessica Chastain won't be joining the "Avengers" universe any time soon.

"Sorry to say that Iron Man 3 isn't going to work out," wrote the in-demand actress on her official Facebook page yesterday. "My schedule is jammed packed and I can't fit anything else in. The press announced my possible attachment far too soon. I know many of you wanted me to be involved, and I'm so sorry to disappoint you. Hopefully there'll be another Marvel film in my future. Shane Black and everyone on the IM3 team are really wonderful. I'm very excited to see the film when it comes out. xx"

Chastain's possible attachment had been rumored early last week, though she was by no means confirmed for the role. The character she would have played was reportedly that of a beautiful scientist who goes head-to-head with protagonist Tony Stark (Robert Downey Jr.).

Other actresses reportedly up for contention in the role Chastain was flirting with are Diane Kruger ("Inglourious Basterds"), Gemma Arterton ("Wrath of the Titans") and Isla Fisher ("Confessions of a Shopaholic"). Thoughts on which of these thesps you'd like to see in the film instead?

News of Chastain's non-involvement follows word that "Avengers" star Scarlett Johansson, who first played the Black Widow in "Iron Man 2",  would also be sitting out the third installment of the Marvel franchise (though she noted that a cameo isn't entirely out of the question).

Chastain will next be seen in John Hillcoat's "Lawless" opposite Tom Hardy, Shia LaBeouf, Gary Oldman, Mia Wasikowska and Guy Pearce. The film hits theaters on August 31.

"Iron Man 3" is set to be directed by Shane Black ("Kiss Kiss Bang Bang") and will star returning cast members Downey Jr., Gwyneth Paltrow and Don Cheadle, with Guy Pearce, Ben Kingsley and Andy Lau joining the franchise for the first time. The film is slated for release on May 3, 2013.

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