One of the more exciting battles entering training camp for many teams is that at backup quarterback. More than 90 percent of the time, who actually wins that battle won’t see an NFL field for more than a few, often meaningless, snaps on a season. Still, it’s always fun to imagine a worst-case scenario being turned around by an unlikely hero in a backup quarterback. Tom Brady got his start that way, as did Tony Romo, and it was the biggest storyline of the Philadelphia Eagles’ first Super Bowl win with Nick Foles.