NFL.com and NFL Network's Ian Rapoport reported that Mendenhall's Achilles injury is minor, according to a person who has spoken with the player. Mendenhall's Achilles tightened up during Thursday night's 26-23 loss to the Tennessee Titans.
Mendenhall's status for the Steelers' next game will be determined by how his Achilles responds over the weekend.
The Steelers struggled mightily to run the football in the three games Mendenhall missed while he recovered from knee surgery. He returned in Week 5 against the Philadelphia Eagles and finished with 101 total yards and one touchdown.
The question becomes if Mendenhall's new injury has anything to do with his speedy recovery from the knee surgery. The Steelers could be more conservative with Mendenhall if they deem that to be the case.
Baron Batch scored a touchdown playing in Mendenhall's place but was held to 22 yards on 10 carries.
Follow Dan Hanzus on Twitter @danhanzus.