Although Marvel Studios has not yet made any official announcement as to who will star in its "Doctor Strange" film, the company is reportedly eyeing Joaquin Phoenix to take on the role of the titular character, according to Collider.

The entertainment news site claims that Marvel has been in negotiations with the actor for the project for a couple of months now. The studio was hoping to get the actor onboard for the film before July so it could make the big announcement during the recent San Diego Comic-Con.

Unfortunately, the actor did not sign the contract in time for the studio's Comic-Con presentation.

Despite the delay, Marvel is still interested in Phoenix to play Doctor Strange. The two parties reportedly met earlier this week to iron out the details of the deal.

The main issue, however, that's preventing the actor from taking on the project has nothing to do with the monetary terms of the project.

The reason why Phoenix is having second thoughts about the Marvel film is because he is unsure if he can work on the project, Collider's sources claims.

According to the insiders, the actor is not comfortable with how Marvel handles its cinematic projects.

The studio is known of conducting numerous re-shoots of film scenes as well as utilizing green screens and visual effects technology for its movies, Badass Digest reported.

In addition, taking on a Marvel film doesn't automatically mean that Phoenix will only do one movie for the studio. An actor's contract with Marvel usually extends across numerous projects.

Samuel Jackson, for instance, has a nine-film deal with the studio while Chris Evans has signed on for six films with the company.

Given these conditions, Phoenix is still thinking twice if he can take on a massive project under Marvel.

Despite not yet having a lead actor, Marvel is still pushing through with the July 8, 2016 release of "Doctor Strange." It will be helmed by Scott Derrickson, the director behind the horror films "The Exorcism of Emily Rose," "Sinister" and "Deliver Us From Evil," according to IGN.

Derrickson will follow the script penned by "Prometheus" co-writer Jon Spaihts.