Pittsburgh Steelers running backs Willie Parker, left, and Frank Summers laugh while stretching before the team's NFL football training camp in...

TAMPA, FL - FEBRUARY 1 : Running back Willie Parker #39 of the Pittsburgh Steelers running with the football against the Arizona Cardinals at Super Bowl...

Baltimore Ravens v Pittsburgh Steelers PITTSBURGH - JANUARY 18: Willie Parker #36 of the Pittsburgh Steelers runs for yardage against the Baltimore Ravens during the AFC Championship...

TAMPA, FL - FEBRUARY 01: Willie Parker #39 of the Pittsburgh Steelers runs the ball in the first quarter against the Arizona Cardinals...

BALTIMORE - DECEMBER 14: Willie Parker #39 of the Pittsburgh Steelers runs the ball against the Baltimore Ravens on December 14, 2008...

PITTSBURGH - JANUARY 18: Willie Parker #36 of the Pittsburgh Steelers runs for yardage against the Baltimore Ravens during the AFC Championship...

Baltimore Ravens v Pittsburgh Steelers PITTSBURGH - JANUARY 18: Willie Parker #36 of the Pittsburgh Steelers runs for yardage against the Baltimore Ravens during the AFC Championship...

Running back Willie Parker #39 of the Pittsburgh Steelers speaks with the media during the AFC Media Day at Raymond...

PITTSBURGH - SEPTEMBER 7: Running back Willie Parker #39 of the Pittsburgh Steelers runs behind the blocking of wide receiver Hines Ward #86 during...

Willie Parker and Edgerrin James

...by Jed Jacobsohn/Getty Images) Cincinnati Bengals v Pittsburgh Steelers PITTSBURGH, PA - NOVEMBER 20: Running back Willie Parker #38 of the Pittsburgh Steelers runs with the football against the Cincinnati Bengals at Heinz Field...

PITTSBURGH, PA - JANUARY 11: Running back Willie Parker #39 of the Pittsburgh Steelers runs for a long gain against the San Diego Chargers at...

BALTIMORE - DECEMBER 14: Willie Parker #39 of the Pittsburgh Steelers is stopped on a run by Corey Ivy #35 of the...

...Rutherford, New Jersey. The Eagles defeated the Giants 23-11. PITTSBURGH, PA - JANUARY 11: Running back Willie Parker #39 of the Pittsburgh Steelers celebrates a touchdown against the San Diego Chargers at Heinz Field...

Jan 11, 2009; Pittsburgh, PA, USA; Pittsburgh Steelers running back Willie Parker (39) runs against the San Diego Chargers in the AFC Divisional Playoff game at Heinz Field...