Mark Wahlberg has revealed he never gave up training for The Fighter, even in between his other films.
Ever since the Other Guys star learnt he would play welterweight boxer 'Irish' Micky Ward, who fought his way to an unlikely world championship, he has continued his training over the last four-and-a-half years.
"I never stopped training, even when I was making other movies - those four-and-a-half years turned out to be the best thing for me," he told Deadline.
"It was about being believable as a guy who could win the welterweight title, and not look like an actor who could maybe box a little bit. If somebody had come to me and said, you're going to have to train that long to make a movie, I'd have said, I'm fairly athletic and willing to work hard; I can do this in six months."
Mark built a boxing ring in his garden, hired two trainers, and trained hours each day to hone his skills.
Christian Bale lost 30 pounds to play Micky's half-brother crack addict Dicky Eklund.
"I wasn't really surprised - I'd seen The Machinist and Rescue Dawn. It was such a big commitment to the role, and a risky move in some ways, but I just knew he would be willing to go there," said Mark of his co-star.