There isn't much to say about this other than Warner should go for significant casting, pairing up a duo well known for having played iconic boxer characters. Robert DeNiro and Sylvester Stallone, perhaps? Or are they not elderly enough? Jon Voight and Ryan O'Neal? Probably not a big enough draw there. Anthony Hopkins and James Earl Jones? Louis Gosset Jr. and Klaus Maria Brandauer? Jimmie Walker and Gary Morgan (in a kangaroo suit)? Stacy Keach and Jeff Bridges? Muhammad Ali and George Foreman? I could go on and on with some great mash-ups from classic boxing films, but you know Warners is at least eying two predictable front runners for the roles of lifelong rivals Billy "The Kid" McGuigan and Henry "Razor" Sharp: Clint Eastwood and Morgan Freeman. Or maybe Freeman and Jack Nicholson. Warner Bros. put out The Bucket List and Million Dollar Baby, so either would fit their interests. Maybe Eastwood and Freeman can be the boxers while Nicholson plays an old promoter?
Who would you like to see play the aged pugilits?