The NFL has suspended 23-year old linebacker Gerald McRath for the first four games of the 2010 season due to him testing positive for performance enhancing drugs.  McRath played in all 16 games for the Titans as a rookie last season and he finished up with 47 tackles, 1 tackle for a loss, 1 pass defensed and 1 interception.  McRath was practicing with the first team this summer at outside linebacker for the Titans.  Rookie Rennie Curran will battle veterans Stanford Keglar and David Thornton for P.T. at outside linebacker until McRath returns to action.