Mark Ruffalo has revealed that all is not yet confirmed for drama Foxcatcher.

The Avengers Assemble star confirmed that he has been in talks to play Olympic gold medal-winning wrestler David Schultz in Bennett Miller's long-in-the-making film, but admitted final details are still being discussed.

"It seems to be true, yes. We're still working out the deal, but I'd like to see it work out," he said.

Mark - who portrays the Incredible Hulk in Joss Whedon's superhero blockbuster - is expected to join Steve Carell and Channing Tatum in the movie, which has been written by E Max Frye and Dan Futterman and is based on a true story.

Steve is tipped to play John du Pont, a paranoid schizophrenic and heir to the du Pont chemical fortune, who built a wrestling training centre called Team Foxcatcher.

Channing is attached to portray Mark Schultz, David's younger brother who was also an Olympic champion wrestler.

Mark is perfect for the role as he followed in his father's footsteps and won some medals as a wrestler in his student days.