New York Daily News' report points out that Stallone was seen exiting the same Atlanta hotel that the movie's cast stays in with what appeared to be a script in hand, only to get in a car usually assigned to Chris Pratt. Marvel Studios has not yet responded to the outlet's request for comment. However, while the report points out several links between Stallone's whereabouts and the film, the evidence is only circumstantial at the moment, and simply visiting a set does not mean an actor has a role in the production.
Stallone recently received an Oscar nomination for reprising his famous role as Rocky Balboa in "Creed," and is also known for action roles including "Rambo" and the comic book-based "Judge Dredd." He's also recently starred in "The Expendables" franchise.