Matt Damon is "inspired" by Christian Bale.

Matt Damon and Christian Bale for GQ

Matt Damon and Christian Bale for GQ

The 48-year-old actor stars with Christian in the upcoming racing blockbuster 'Le Mans '66' - which is titled 'Ford v Ferrari' in the US - and has said he is amazed by the "approach" his co-star takes when it comes to his roles.

In a joint interview with Christian for the November issue of GQ magazine - which hits newsstands on Friday (04.10.19) - he said: "Christian's approach is the approach that young actors wish they had when they're talking s**t: a monk-like discipline in service of your work. That's one of the rarest things, because it comes at a price. It is inspiring."

And the 45-year-old star says he picked up many of his own acting techniques from one of first ever roles, which saw him act alongside Rowan Atkinson, the star best known for playing Mr. Bean.

Christian was "mesmerised" watching the actor perform, as he was stunned by the way he managed to "become" his character before getting on stage.

He said: "One of [my] first jobs ever was with Rowan Atkinson and I think I look at him as the template. He was playing ... 'The Nerd', it was called, by Larry Shue. He would come out, we'd say hello, but he didn't really socialise. None of us knew him - it was before he did Mr Bean. And he would just become this character, but before he went on stage. And I would just watch him; I would see him becoming a character. I was mesmerised. And then he just stayed in character for the whole night. And it wasn't until the whole thing was finished that he invited me to say hello and that I actually spoke to him for the first time. It dawned on me that was my learning phase. I went, 'Oh, that's how it's done then, is it? OK, great.' "

Although both Matt and Christian have had lucrative careers, they now admit it's getting harder for them to transform for their roles, because they have "aches and pains" now they're older.

Christian said: "You start hitting a certain age when your aches and pains aren't going away any more. You start realising you're not bouncing back the way you used to."

Whilst Matt added: "De Niro said to me when we were making 'The Good Shepherd' - we were talking about weight loss and weight gain - [how] he did 'Raging Bull' when he was 35. He said, 'I was very specific about that being the age. I would not do it beyond that. Because it's too much on your body after that.' And also, you kind of keep it with you forever if you do it after that. "