Extra no more: How former Alabama player Caleb Castille landed the role of Tony Nathan in Woodlawn

Caleb Castille figured if he couldn't play running back Tony Nathan with his helmet off, he might be able to play the Alabama great with his helmet on. Castille, a former Alabama walk-on defensive back whose father (Jeremiah) and brothers (Tim and Simeon) also played for the Crimson Tide, had auditioned for the lead role in Woodlawn. Instead, the part went to a British actor named Osy Ikhile.

So, last year Castille found himself on a field in his hometown of Birmingham, Ala., with 500 other hopefuls trying to win parts as football players in the story of Nathan's high school career—which took place in the early 1970s shortly after the forced integration of Alabama's public schools. The Birmingham native had no idea when he went to that tryout that he'd wind up starring in the movie alongside Academy Award winner Jon Voight and one-time Goonie, Rudy and hobbit Sean Astin. On Friday, Castille will make his silver-screen debut when the faith-based Woodlawn opens nationwide.

When Mark Ellis looked at his stopwatch after Castille ran the 40-yard dash at that tryout he was immediately intrigued. Ellis was Woodlawn's sports coordinator. Over the past 20 years, the former Appalachian State football player has built a reputation for staging realistic sports action. If you've watched a movie that includes a football game, you've probably seen Ellis's work. He coordinated scenes and acquired and trained athlete extras for Invincible, the remake of The Longest Yard, Varsity Blues and dozens of other films. That scene in The Dark Knight Rises when Bane blows up a football field? Ellis coordinated the game action. He also did the football scenes in Not Another Teen Movie, which parodied, among other films, Varsity Blues. "You know you've made it when you can spoof your own movie," Ellis says.

Castille had spent three seasons playing for Alabama. He was on the 2011 and '12 national title teams before leaving the sport to pursue acting. He auditioned alongside former players from all three NCAA divisions, but Castille moved so much better than the rest of those in attendance. He also moved quickly. Ellis looked down and saw four-point-four-something and knew he needed to watch Castille closely. When Ellis brought out the footballs on the third day of the tryout and watched Castille play in seven-on-seven drills, he realized he'd found his body double for the Nathan character.

For insurance reasons—and also because most aren't good enough athletes—the majority of actors require a double if their character is going to take punishment in a sports movie. Mark Wahlberg had two such doubles (including former Florida wide receiver Travis McGriff) when he played Vince Papale in Invincible. The original plan was that Castille would portray Nathan when he was doing anything athletic on the field or when he was getting hit. "A little movie magic," Castille says.

Then the plan changed.

When Ellis does a football movie, he holds a training camp not unlike the preseason camp for a real football team. This allows the athlete extras to develop a sense of team chemistry and gives filmmakers a chance to teach them the plays they'll need to run once shooting begins. Castille was the star of the camp. "I'm just putting in the plays," Ellis says. "He can do everything I'm asking, so now I'm getting creative. I'm putting in spins and broken tackles."

Meanwhile, Ikhile was an ocean away.

Ellis kept asking filmmakers Andrew and Jon Erwin the same question. When do I get the real guy? Ellis had never done a training camp without his lead actor, and while Ikhile had played rugby, he hadn't played football. The filmmakers told Ellis that Ikhile was having some minor visa issues, but he'd make it in time for filming. Then, on Halloween of last year, Ellis got a call.

It was Andrew Erwin. Principal photography was set to begin the next week, but Ikhile's visa problems were going to keep him in the United Kingdom. Ellis knew the next question would be about Castille. "What do you think? Can he do it?"

Ellis couldn't help but think some higher power had intervened. "The other star can't get here," Ellis says. "This kid has wanted the role since the beginning. Is this meant to be?"

Castille got a call from the filmmakers at about the same time. "They called me three days before production," he says. "They explained the whole thing with the visa issues and said I was one of the guys. They were like, 'We're going to give you every opportunity to win the role.' Next thing I know, I'm Tony."

Suddenly, the guy who practiced alongside future NFL first-round draft picks Dre Kirkpatrick and Dee Milliner and who had previously landed a role as the "guy throwing football at the cookout" in the music video for country singer David Nail's "Whatever She's Got" was about to get a significant upgrade to his IMDB page.

(Caleb Castille, No. 17) Bill Frakes/SI

Castille attacked the role, and it became clear to the cast and crew Castille has the chops to make acting his career. "I really felt like the camera would love this kid. There's just something behind his eyes. He's so real. He's so authentic," Ellis says. "The camera ate him up."

During filming Castille got to learn from his veteran castmates. He was especially honored to work alongside Voight, who disappeared into the role of Bear Bryant. When Castille's father, who played for Bryant, visited the set and saw Voight in costume, Castille knew the filmmakers had nailed the look. "The first time my dad stepped on set and saw Jon dressed as Bear Bryant, it was so emotional for him," Castille says.

Castille, meanwhile, was thrilled Voight finally got to play a coach for an entire movie without enduring a player mutiny. "I'm a Varsity Blues guy," Castille says. Castille said some athlete extras wound up getting assigned nicknames from that movie. When the camera wasn't rolling, Woodlawn High also had a Tweeder and a Billy Bob. Did Castille nab Moxon for himself? "I was Tony, bro," he says.

Castille still can't believe the serendipity that allowed a kid from Birmingham to play one of its favorite sons on the big screen. "It's an honor," he says. "It's playing your hometown hero. Who gets to do that?"

Castille is currently plotting his next move in Hollywood. He might land a role in a war movie next year, and said a few producers have approached him about television roles. It's all because he embraced the "next man up" philosophy he learned playing football.

"I believe there's always room to grow. There's always room to improve. I'm just working every day—just like on the football field," Castille says. "I want to be the best actor I can be. I want to be on the scale of the ones who win an Oscar."