Dwayne 'The Rock' Johnson has reached a "turning point" in his acting career.

The wrestler-turned-movie star plays real life MMA fighter Mark Kerr in sports drama The Smashing Machine and he's admitted the job "completely changed" his life even though it didn't do as well as expected at the box office - because Johnson wasn't worried at all about the numbers.

During an appearance on The Hollywood Reporter's Awards Chatter podcast, he explained: "Smashing Machine completely changed my life in ways that I didn't anticipate, because of what it represents.

"It represents, for me, listening to your gut, to your instinct, to that little voice. Sometimes in life, you think you're capable of something, but you don't quite know. And sometimes it takes people around you to go: 'Come on, you could do this.'

"Smashing Machine also represents a turning point in my career that I've wanted for a long time: for the first time in my career ---20 plus years since The Scorpion King came out - I made a film to challenge myself and to really rip myself open and to go elsewhere and disappear and transform.

"And not one time did I think about box office."

He went on to add: "Even though we didn't do well [at the box office], or as well as we wanted to, it was okay because it just represented the thing I did for me.

"Maybe it was because I was an only child, but all the stuff that I had experienced as a kid and as a teenager - eviction, my mom tried to take her life two months after we got evicted and I pulled her out of the middle of the highway, a whole bunch of stuff happened - I had rejected exploring any of that on film.

"For years I would do these other films that were big and fun, Jumanji and Moana, with a happy ending, and I love that still.

"But what this represented was: 'Oh wait, I can do the thing I love, which is to tell stories, but I could also take all this stuff and have a place to put it'."

Johnson went on to reveal he's going to take his experience on The Smashing Machine and pour it into his upcoming projects with directors Martin Scorsese and Darren Aronofsky.

He added: "So you ask if I'm going to run towards this? We have a project with Scorsese, a project with Aronofsky. Yes, I'm going to run, put all my s*** in that, and continue to challenge myself.

"Anyway, Smashing Machine, as you see, was an opportunity of a lifetime that did change my life."