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Miles Teller pulled a Chris Pratt and got all buff for a new movie role.

The "Whiplash" star debuted his six-pack abs on Tuesday's "The Tonight Show" when he brought along before and after shirtless pics of himself that revealed his progress in the gym. "You don't know what I'm rocking under this suit," he bragged to host Jimmy Fallon.

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The 28-year-old actor bulked up to take on the role of real-life World Champion Boxer Vinny Pazienza in "Bleed for This." After an almost fatal car accident, it was uncertain if Pazienza would ever walk again, but he recovered and made a historic comeback.

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Another noticeable change on Teller in this movie, his facial hair. "I take a long time to grow some facial hair, man," he admitted to Fallon. "Everyone has their strengths. I'm a great dancer, I have good hair, I don't have, like, weird body hair."


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