Raiders add another mediocre, injury-prone player

The Oakland Raiders added defensive tackle William Joseph, a former New York Giants first-round pick. The 300-pounder missed 2007 and has contributed just 72 tackles and seven sacks in five seasons.

He joins a collection of free agents signed by the Raiders this season, most of whom are talented, but injury-prone and/or underachieving. They include tackle Kwame Harris, safety Gibril Wilson, and wide receiver Javon Walker.

The team also shelled out $18 million in guarantees to keep defensive tackle Tommy Kelly.