The folk frontman was hoping to land his first acting role in the film, which is loosely based on the memoir of struggling cult singer Dave Van Ronk, but, after watching the finished product, he is happy to have lost the job to Hollywood newcomer Oscar Isaac.
Sitting down for a chat with Isaac for Interview magazine, he said, "I know I told you this when we met, but I tried out for your role in Inside Llewyn Davis - and thank God for everyone that I didn't get it. But they auditioned a lot of musicians and actors for this part, to the point where I heard the Coen brothers and T Bone Burnett (executive music producer) say that they had more or less given up on the idea of finding someone. And then you appeared."
During the interview, Isaac, who performed in a series of bands during his youth, admitted the acting gig allowed him to realise his musical dreams in front of a whole new audience.
He explained, "What was also interesting for me about playing those songs in those scenes was that, obviously, I needed to play this character, Llewyn Davis, who has a very particular voice and is playing a very particular style of music. But doing that was also an opportunity for me, Oscar, to be the musician that I'd always wanted to be as a kid - and to actually sing with that kind of honest voice that I'd always wanted to sing with."
Oberst got the chance to become involved in the film project by performing as part of the line-up for the Another Day, Another Time: Celebrating the Music of Inside Llewyn Davis benefit concert in New York in September (13). The three-hour show, organised by the movie's directors Joel and Ethan Cohen and producer Burnett, also featured Patti Smith, Jack White, Marcus Mumford, Elvis Costello, The Avett Brothers and Joan Baez, while Isaac and his movie co-star Carey Mulligan took the stage too.