Before Zoe Saldana was cast, Gina Carano, Adrianne Palicki, Olivia Wilde and Rachel Nichols were considered for the role of Gamora.
Jim Carrey and Adam Sandler were considered for the role of Rocket Raccoon.
Jason Momoa, Dominic Purcell, Brian Patrick Wade and Isaiah Mustafa were considered for the role of Drax the Destroyer before Dave Bautista was cast.
Joseph Gordon-Levitt, Jim Sturgess, Joel Edgerton, John Krasinski, Zachary Levi, Sullivan Stapleton, Eddie Redmayne, Lee Pace, Jack Huston, Garrett Hedlund, Michael Rosenbaum, Wes Bentley, Chris Lowell, Cam Gigandet, Aaron Paul, Jensen Ackles, Logan Marshall-Green and James Marsden were all considered for the role of Peter Quill/Star Lord before Chris Pratt took the role.
Peyton Reed and Anna Boden and Ryan Fleck were considered to direct before James Gunn took the job.