Robert Duvall on '12 Mighty Orphans,' his proudest performance and the major role he turned down

Acting is Robert Duvall's first love, but football ranks a very close second. 

Someone once said that "American football is the greatest game ever invented, and I would have to go along with that," says Duvall, 90, who played defensive back on his high school team growing up in St. Louis. 

So it's no surprise that the seven-time Oscar nominee (and proud Clemson Tigers fan) was drawn to football drama "12 Mighty Orphans" (now playing in theaters in Texas; opens nationwide Friday). Based on Jim Dent's 2008 book, the film tells the true story of the Mighty Mites, an underdog football team from a Fort Worth, Texas, orphanage that went all the way to the state championships in the 1930s. Luke Wilson and Martin Sheen play coaches, while Duvall makes a cameo appearance as former orphan Mason Hawk, who helps finance their efforts.