Spader was confirmed earlier this month to play "high-class Jedi warrior-like" CEO Robert California on the upcoming eighth season of the NBC comedy.
Crazy, Stupid Love star Carell told Access Hollywood that he is excited about the changes that Spader will bring to The Office and was delighted upon hearing that the former Boston Legal actor had taken over his spot.
Carell said: "I think it's an excellent choice. I think it's great and he will infuse all this new energy into the show."
"In talking to the cast, everyone's very excited and I know it'll be a good season."
Catherine Tate was previously tipped for the role following Carell's recent departure.
Spader appeared in The Office's season seven finale as an applicant for Michael Scott's (Carell) open manager position at Dunder Mifflin alongside Tate.
The eighth season of The Office will premiere on Thursday, September 22 at 9/8c on NBC.