When The Muppets hits theaters the day before Thanksgiving the movie will be missing one of the original “Muppeteers”: Frank Oz.

Before becoming a director with films as diverse as the 1986 musical remake of Little Shop of Horrors and the DeNiro/Brando/Norton crime drama The Score to his credit, Oz provided the voices and movements for several of the most iconic Muppet characters including Miss Piggy, Fozzie Bear, and Animal as well as Grover and Cookie Monster on Sesame Street. He also did the voice and puppeteering for Yoda in the original Star Wars trilogy (for the prequels Oz only did the voice, as Yoda was now a CGI character).

Oz, whose parents were both puppeteers (and also Holocaust survivors who fought the Nazis with the Dutch Brigades), continues to work in the field occasionally to this day but is mostly retired.

But according to a recent interview with the British website Metro, the 67-year-old Oz revealed that he was invited to be part of the new Muppets movie being directed by James Bobin (Flight of the Conchords) and starring Jason Segel (who also co-wrote) and Amy Adams, but that he rejected the offer.

Back in 2006 Oz was approached by Dick Cook, then the chairman of the Walt Disney Company, to possibly write and direct a new Muppets movie. While Oz was developing the script along with the studio’s special effects department Disney executives were buying another pitch for a Muppets movie from Segel, whose career was then just starting to kick into gear thanks to his involvement in the hit movies Knocked Up and Forgetting Sarah Marshall (the latter directed by Nicholas Stoller, Segel’s writing partner on The Muppets). The decision to go with Segel and Stoller’s script over Oz’s rankled the Muppet faithful, leading one veteran to wonder if “this is a case of Disney wanting to get into the Jason Segel business” instead of making a movie true to the characters and Henson’s vision.

Oz isn’t the only former Muppets cast member expressing his doubts about The Muppets; THR posted an article recently in which several unnamed veterans of the Muppets troupe, including a few who worked on the movie, voiced their disapproval of the direction the beloved characters seem to be going in under the guidance of Segel and Bobin. The decision to have The Muppets open with Henson’s creations having gone through a bitter breakup and the presence of some lowbrow gags, including Fozzie’s “fart shoes” (shown in the trailers), are just two bones of contention with the old school players. “They’re looking at the script on a joke-by-joke basis, rather than as a construction of character and story,” said one unnamed source. Those same Muppet performers at one point considered removing their names from the credits but ultimately decided against it because their efforts would have had little-to-no effect on the corporate mindset at Disney. One performer was quoted as saying, “It doesn’t send any message. Disney wouldn’t care.”

Bonnie Erickson, executive director of the Jim Henson Legacy (the organization dedicated to keeping the late Henson’s work in the public eye) as well as the designer of the original Miss Piggy, is ambivalent about how the new movie will be received by the public but she remains optimistic as well: “I’m hoping the standard of excellence that Jim set is maintained.”

The Muppets opens on November 23, 2011.