1. John Krasinkski as Captain America Rodin Eckenroth / Getty Images, Marvel John auditioned for the role in the 2011 movie, but received a call from his agent that he didn't get the part. He took the news pretty well, even if it was delivered to him on Emily Blunt's birthday."My agent called and said, 'They're going to go with Chris Evans. And I remember I said, 'Yeah, look at him. He's Captain America.'" Emily asked if he wanted to cancel her birthday dinner plans, but John replied, "It's Chris Evans. Of course we're going to dinner." 2. David Duchovny as The Hulk Michael Loccisano / Getty Images, Marvel The Hulk has been played by several popular actors over the years, but before Edward Norton landed the role for the 2008 film, X Files star David Duchovny auditioned for it. Marvel vice-chairman, Peter Cuneo, said David was a frontrunner for the part, after Eric Bana pulled out of the sequel project. Why David didn't get role is still a mystery.The role was eventually taken over by Mark Ruffalo. 3. Liam Hemsworth as Thor Frazer Harrison / Getty Images, Marvel When Chris initially auditioned for the role of Thor, he didn't get a single call back. He then found out his younger brother Liam tried out for the same role and received a ton of callbacks. Ultimately, none of the actors were cast in the role. But after seeing how far Liam got in the audition process, Chris's manager decided to ask if he could get another chance to audition."I did an audition in Vancouver in this hotel room with my mum reading Anthony Hopkins' part.," Chris told W magazine. "I came in kind of with a little, I guess, motivation and maybe frustration that my little brother had gotten further than me. It's a little family, sibling rivalry sort of kicked up in me." 4. Wesley Snipes as Black Panther Kevin Winter / Getty Images For those who don't know, the story of Black Panther was in the works to hit big screen in the mid '90s, way before Chadwick Boseman landed the role. At the time, Wesley Snipes was ready to bring the character to life. Unfortunately, multiple script rewrites, low quality CGI technology, storyline disagreements, and director changes prevented him from bringing the story into fruition. "We went through three different scripts and a couple of different director options — very interesting director options at the time," Wesley Snipes told The Hollywood Reporter. 5. Sam Rockwell as Iron Man Mike Coppola / Getty Images, Marvel Sam Rockwell was considered for the role of Iron Man, but the part ultimately went to Robert Downey Jr. However, director Jon Favreau saw something in him, which is why they offered him a role in Iron Man 2 as the villain, Justin Hammer. And in a way, Sam still found a way to play Tony Stark...kind of."Jon had called me about possibly screen-testing for the part of Tony Stark in Iron Man," Sam Rockwell told The A.V. Club. "And whatever happened, I think I was out of the running. Robert just killed it, you know, and I never heard anything after that. We gave Justin Hammer the glasses and kind of sleazed him up a little. It was a chance to do Tony Stark." 6. Emily Blunt as Black Widow John Phillips / Getty Images, Marvel Although Emily Blunt continues to shut down rumors that she was initially offered the role of Captain Marvel, Emily did admit to being the frontrunner for two other heroes: Black Widow and Peggy Carter. Scheduling issues prevented her from taking the roles. "It was never the right time, really, and it just didn’t work out scheduling-wise with those two. It just wasn’t the right time," Emily Blunt told Vulture. 7. Glenn Howerton as Star-Lord Astrid Stawiarz / Getty Images, Marvel It's Always Sunny in Philadelphia star Glenn Howerton came pretty close to playing Star-Lord in Guardians of the Galaxy. In fact, the film's director, James Gunn, admitted Glenn was his second choice if Chris Pratt didn't work out."Glenn came along a little bit later,” said James Gunn. “But there was a good chance that, if I didn’t cast Chris, that I would’ve cast Glenn Howerton in the role." 8. Olivia Wilde as Gamora Kimberly White / Getty Images, Marvel Olivia Wilde was offered the role of Gamora in the first Guardians of the Galaxy film, but turned it down for unknown reasons. The part was later given to Zoe Saldana.In a interview with Cinema Blend, Olivia opened up about female superheroes and why she dislikes their "perfect" persona: "I think when they are translated into film, the women can become these ultimate goddesses of perfection, and I would love to create a female Marvel character who is unexpected and complex. 9. Saoirse Ronan as Scarlet Witch Jon Kopaloff / Getty Images, Marvel Marvel reportedly used Saoirse Ronan as the prototype for Scarlet Witch during the development process, so it's no wonder she showed interest in playing the role. It's unknown what steps were taken after that, but the part ultimately went to Elizabeth Olsen. 10. Joseph Gordon-Levitt as Ant-Man Frazer Harrison / Getty Images, Marvel Joseph Gordon-Levitt auditioned for the role of Ant-Man and eventually became a part of the director's top two choices. Ultimately, the part went to the other frontrunner, Paul Rudd. 11. Joaquin Phoenix as Doctor Strange Matt Winkelmeyer / Getty Images, Marvel Joaquin Phoenix was also in the running to play Doctor Strange, making himself a leading contender for the role. Joaquin released a super vague statement explaining why he turned down the role:"I think they make some great, fun movies. There's nothing wrong... I'm not a fucking, like, cinephile. I think they keep the fucking industry going in some ways, so I don't have a problem with it at all. I think everybody was really happy with how things turned out. All parties were satisfied." 12. Jason Momoa as Drax the Destroyer Angela Weiss / AFP / Getty Images, Marvel Jason Momoa had his eyes set on playing Drax and came really close to landing the role. Jason turned down the role, because Drax was too similar to characters he'd portrayed in the past. Jason feared getting typecast as the "brute.""I've been there and done that, whether people have seen it or not," said Jason Momoa. "You want to stretch." 13. Matthew McConaughey as Ego. Tristan Fewings / Getty Images, Marvel Matthew McConaughey was considered for the role of Ego, Peter Quill (Star-Lord)'s father in Guardians of the Galaxy. Matthew turned down the role for reasons that have yet to be revealed. Ultimately, Kurt Russell nabbed the role. Avengers: Endgame is in theaters now, so if you want to obsess about the movie with us, check out more of our Marvel coverage here.