Sly: Directing 'Expendables' was a challenge

Sylvester Stallone found it difficult directing his 'Expendables' co-stars.

The actor-and-filmmaker - who appears in the action blockbuster alongside Bruce Willis, Mickey Rourke, Jason Statham, Dolph Lundgren and Arnold Schwarzenegger - admits it was tough trying to convince his cast to try new things on set.

He said: "Was it tough? Yes. You get these strong men who have a certain way of doing things on a film, and you have to get them to give that up.

"Like Jason in this film is totally different than in anything he's ever done. Dolph Lundgren is totally different."

Despite his difficulties, the 64-year-old Hollywood star was thrilled to be able to get so many action legends involved in the project.

He added: "The thing was to find certain personalities and put them all together like a dream team.

"I wanted to do a film a bit like 'the Magnificent Seven' or 'The Dirty Dozen'. One of those that only comes along once in a while."