Update: 5 Seahawks backups out; Bates back

Backup center Lemuel Jeanpierre is out for the season with an unspecified neck injury and second-year cornerback  Tharold Simon, who missed more than a week of practice, is expected to have surgery on an injured knee. The Seahawks will go into Thursday’s opener at the Clink against Green Bay with just eight offensive linemen.

Jeanpierre was placed on injured reserve. If the Seahawks need to relieve starter Max  Unger, former Bellevue High School star Stephen Schilling, signed in the offseason as a free agent from San Diego, will fill in despite his meager reps as a center. Jeanpierre’s roster spot was taken by WR Phil Bates, who was cut Sunday and re-signed Wednesday.

Simon missed more than a week of practice with a knee problem, which helps explain why the Seahawks traded a sixth-round draft pick Sunday to the Colts for CB Marcus Burley.

“He’s got real minor stuff to get done,” Carroll said after a short practice Wednesday. “We’ve got to get some things cleaned up. We’re going to try to do this really quickly. If all stays on course, he’ll get a little something done the next couple days.”

Burley, who played college ball at FCS Delaware, was on the practice squads of four teams in his first two years in the NFL but has not played in a game, will join DeShawn Shead as the backup cornerbacks for the NFL regular season opener.

Also ruled out of the game were tight end Cooper Helfet (knee), running back Christine Michael (hamstring) and linebacker Kevin Pierre-Louis (hamstring).

Linebacker Bruce Irvin (hip) and receiver Kevin Norwood (ankle) are listed as probable and expected to be available after returning to practice. Irvin missed the entire exhibition season while recovering from June 1 hip surgery. Norwood practiced just one day in training camp before needing surgery to remove bone spurs from his ankle.

Seattle also released three players from the practice squad — WR Chris Matthew, OK Nate Islesv andv DB Terrance Parks. Added were LB Allen Bradford — a former Seahawk who was on the initial 53-man roster last season  before being released — and guards David Arkin of Missouri State and Drew Nowak of Western Michigan.