Miles Teller lost over 19 lbs in five weeks in preparation for his boxing film 'Bleed For This'.

The 29-year-old American actor - who had just two weeks to learn how to drum for his role in musical movie 'Whiplash' - had to step inside the ring to play real-life world champion pugilist Vinny Paz in the biopic and his boxing training resulted in him slimming right down.

In an interview with The Times newspaper, Teller said: ''With pretty much every other boxing movie you've seen, they have a couple of days to shoot each fight. But because ours was bare-bones production, it was just kind of like, go, go, go! With this I only had access to Darrell Foster for five weeks. He trained with Will Smith for months!''

Teller spent six hours in the gym every day - four hours of boxing and two hours of weight training - for five weeks and as well as shifting so many pounds he got down to six per cent body fat.

And he even roped in a dialect coach to help him nail a pitch-perfect blue-collar Rhode Island accent.

Teller plays the role of local Providence boxer Vinny 'The Pazmanian Devil' Paz.

The film is centred on Vinny who shoots to stardom after winning two world title fights. After a near-fatal car accident leaves him with a broken neck, and the news that he may never walk again, with the help of trainer Kevin Rooney played by Aaron Eckhart, against all odds and doctors' orders he returns to the ring 12 months later for what could be the last fight of his life.

In real-life, Teller admitted his facial scars, which he sustained in a car accident, caused him to lose auditions in the past.

He said: ''I remember I had lots of scabs on my face, and at first they'd start to peel away and I was thinking, 'Man, this is crazy! I got in this car accident and I'm going to be fine in a couple of weeks!' But then the scabs fell off and I was left with all these prominent scars that did not heal well at all.''

He described how the scars were visible when he stood in front of the camera at school and it later affected his auditions.

He explained: ''Even when I started going to auditions the feedback my agent got was, 'Miles is really good, but it doesn't make sense for his character to have scars.'''

It lead him to have two years of painful laser therapy but nowadays, he less worried about what he looks like on the big screen.