The biggest story to come out of Dallas Cowboys training camp isn't from the No. 4 overall pick in the draft. Nope, running back Ezekiel Elliott has been sidelined for the first two preseason games. Dak Prescott, a fourth-round pick, has been the star of the preseason for Dallas. While he's garnered national attention for his first two games, one former NFL general manager has a lofty comparison of the rookie.Charley Casserly -- now with NFL.com and former Washington Redskins GM -- had this to say of Prescott:"I don't know how you can't fall in love with him because he's been outstanding.