Byron Maxwell one of six Seahawks players out Sunday

RENTON – Significant injuries are piling up for the Seattle Seahawks, with four starters and two backups out for Sunday’s road game against the St. Louis Rams.

Seahawks coach Pete Carroll said Friday that starting cornerback Byron Maxwell will not play because of a strained calf he suffered last week in the game against the Cowboys.

Other starters already listed as out are middle linebacker Bobby Wagner (turf toe), center Max Unger (foot) and tight end Zach Miller (ankle surgery).

The Seahawks also are thin on the defensive live with defensive tackle Jordan Hill (sprained ankle) and rookie defensive end Cassius Marsh (broken foot) out.

Carroll said Marsh cracked a bone in his foot in practice Wednesday. He will undergo surgery and be out six to eight weeks.

The Seahawks also list backup tight end Luke Willson (groin) and wide receiver Percy Harvin (thigh) as questionable for Sunday.

“Luke has a sore groin, so we rested him again,” Carroll said after practice Friday. “We’ll take it all the way to game time to make sure he’s OK. Percy practiced and got through [Friday].”

With so many players out or questionable, expect the Seahawks to make some roster moves before Sunday’s game. They might bring up rookie tight end RaShaun Allen from the practice squad if Cooper Helfet is the only healthy tight end.

It’s also unlikely they would carry Marsh for six to eight weeks. He probably will be placed on injured reserve.

Carroll would not say who will start in place of Maxwell, but second-year cornerback Tharold Simon will make his NFL debut, whether he starts or not. Simon, who missed his entire rookie season after undergoing two foot surgeries, had minor knee surgery on Sept. 4.

“He looks in top shape and ready to go,” Carroll said of Simon. “He had an excellent week.”

The Seahawks re-signed defensive end Greg Scruggs Tuesday after releasing him last weekend to make room for defensive back Steven Terrell to move up from the practice squad. But Terrell was released Tuesday and later returned to the practice squad.

Scruggs (6-3, 310) played in 12 games as a rookie in 2012, but missed all of last season with a knee injury. He has not been on the active roster this season, but will be part of the defensive line rotation Sunday.

“We like the way he works,” Carroll said of Scruggs. “He’s a good, tough kid. He can play a lot of spots for us.”

K.J. Wright will move from an outside linebacker spot to start for Wagner, who is in a cast and is likely to miss several games.