RENTON - Seahawks rookie offensive lineman John Moffitt will be out for the rest of the season because he needs to undergo surgery to repair his right knee, after he suffered an injury in the first quarter of Sunday's game.

Moffit was chosen in the third round out of Wisconsin and had started all nine games for Seattle this season. He suffered injuries to medial-collateral ligament (MCL) and post-collateral ligament (PCL). His anterior-cruciate ligament (ACL) is OK, which means his recovery should proceed faster.

Moffitt was replaced in Sunday's game by Lemuel Jeanpierre. Paul McQuistan also may be a consideration to take Moffitt's spot going forward.

"We'll figure that out," coach Pete Carroll said.

The injury comes at a time as Seattle's offensive line has shown improvement, allowing only two sacks over the previous two games.

"He has been working so hard at it, and has been such a big part, too," Carroll said of Moffitt. "Good character in the locker room, and all. A good guy. He's really right at the cusp of when we're starting to improve, he would have loved to have been part of this as he finished the season. We'll get him right."

Seattle had three players leave Sunday's game with concussions: receivers Doug Baldwin and Sidney Rice and safety Kam Chancellor. Carroll said all three have shown positive signs in recovery and should have a chance to be available Sunday, however, the team won't know until the week progresses.