An unusual path to the NFL

I remember a running back for the Denver Broncos a few years back had a similarly strange path to being in the National Football League, but I can't remember his name.

But I'd say that is one of the only, if not the only, people with a similar story as Ahmard Hall, the fullback for the Tennessee Titans:

A fourth-year NFL veteran, Hall, 30, served four years in the Marines, with tours of duty as a sergeant in Kosovo and Afghanistan, before resuming his football career as a walk-on at Texas in 2004. He secured a spot on the Longhorns' roster by writing a letter to Mack Brown, and the Texas head coach was so impressed by the impassioned missive that he waived a school rule stipulating that walk-on candidates had to have played organized football within the past 24 months. Hall signed with the Titans as a free agent after no team selected him in the 2006 supplemental draft.

Afghanistan war veteran, turned Texas Longhorn, turned undrafted player, turned NFL regular. Not exactly the same career path as Peyton Manning.