Foster missed eight games due to injury in 2013, compiling 542 yards rushing and one touchdown. Carrying the weight of 956 rushing attempts in three seasons from 2010 to 2012 has critics wondering if the back issue is a sign that the 27-year-old is beginning to decline.
For his part, Foster doesn't believe he has to validate anyone else's expectations.
"It's not like I've got to go prove -- I'm not trying to prove anything," Foster said. "I always play this game to the best of my ability and that's what I'm going to continue to do."