The Pittsburgh Steelers will likely be without RB Willie Parker for the next two weeks due to a sprained knee.  Parker was off to a good start this season for the Steelers having rushed for 263 yards on 66 carries (4.0 ypc) with 3 TD runs.  Parker will be replaced in the starting lineup by rookie Rashard Mendenhall.  Mendenhall has carried the ball 10 times for 28 yards (2.8 ypc) and he has caught 1 pass for 11 yards this season.  He also has returned 6 kickoffs for 115 yards (19.2 avg) so far this season.  Mendenhall made a huge rookie mistake however when he texted fellow rookie RB Ray Rice of the Ravens and advised him that he would run all over the Ravens’ defense giving them bulletin board material.  We’ll see if he can back up his tough talk on Monday Night Football.  Mewelde Moore will be Mendenhall’s top backup at RB and he will replace him as the kick returner.  Moore has carried the ball 1 time for 6 yards this season and he has returned 2 kickoffs for 33 yards (16.5 avg).  The Steelers will miss Parker’s speed against the Ravens and Jaguars.