SANTA CLARA, Calif. -- Seven seasons after walking away from the San Francisco 49ers and the NFL, running back Glen Coffee is attempting a comeback.

The NFL reinstated Coffee from the reserve/retired list on Friday afternoon after he walked away from the game in August 2010. At the time, Coffee was entering his second NFL season but told reporters that "God had a bigger plan" for him.

He served with the sixth Ranger Training Battalion as a U.S. Army paratrooper for four years starting in 2013.

Glen Coffee last saw NFL action in 2009, when he gained 302 total rushing and receiving yards and scored one touchdown for the 49ers. Paul Sakuma/AP Photo

In his lone NFL season, Coffee rushed for 226 yards and a touchdown on 83 carries, and he also had 11 receptions for 78 yards.

In conjunction with his reinstatement, the 49ers released Coffee on Friday, giving him an opportunity to start anew at 29. Coffee's agent told NBC Sports Bay Area that Coffee is in great shape and has been training in Tuscaloosa, Alabama.

If Coffee goes unclaimed on waivers, the next step will be to work toward setting up workouts for interested teams.

The Niners originally selected Coffee in the third round of the 2009 NFL draft after a strong college career at Alabama, where he rushed for 2,107 yards and had 14 touchdowns.