What went wrong? Running backs

While it's easy to blame the Texans' 2013 season on one position, their unexpected fall to the worst record in the league featured problems at nearly every position on the field.

Thus, a series detailing what happened at each position on the field.

We started Thursday with safeties.

We continue Friday with running backs.

Key players: Arian Foster, Ben Tate, Dennis Johnson, Deji Karim, Jonathan Grimes

What went wrong: This sordid tale was too much for the Texans to overcome as their offense is dependent on a successful running game. It started with Foster, who missed the entire preseason with calf and back injuries. Foster started the first game of the season and then in the second game powered his way into the end zone for a two-point conversion that led to overtime. That was Houston's last win of the season. Foster dealt with a back injury, trying to play through it. He played in eight games, but didn't carry the ball in the eighth and had surgery two weeks later. That led to Tate becoming the starter. Tate broke his ribs against the Kansas City Chiefs but played through that, showing his toughness in a contract year, because he was the last running back the Texans had left that day. Houston had sent Cierre Wood home the night before and cut him on Monday. Tate played in several games with the broken ribs, but he, too, finished the season on injured reserve. Then came Johnson (another undrafted rookie, who couldn't finish the season because of a hip injury), Deji Karim (who suffered a broken collarbone) and finally Grimes. Grimes made it through that final game without an injury. He was a street free agent until the Texans signed him on Dec. 18 and started 11 days later.

Reason for hope: This one's tricky as it comes with a lot of unknowns. Will Foster come back completely healthy? Who will the Texans second- and third-stringers be? Tate becomes a free agent in March and one of those players could come in the draft.