While Lynch's absence was expected following abdominal surgery last week, head coach Pete Carroll had been optimistic about Richardson's chances to play. Instead, Richardson was unable to practice all week and was officially ruled out on Friday.
''His hamstring just isn't coming back,'' Carroll said. ''We're just disappointed that he wasn't able to continue to get back and it's just lingered a little bit.''
Carroll said it's unlikely Richardson will be back next week and didn't rule out the possibility of making a roster move, which could mean placing Richardson on injured reserve.
Dobbs and Hill are rotational players for Seattle who serve mainly as interior pass rushers. Francis is more of a run-stopper, which could be useful against Adrian Peterson this week.
Fullback Will Tukuafu is questionable to play after suffering a concussion as well. He's been a limited participant in practice the last two days. With Tukuafu also able to play along the defensive line, his availability for Sunday's game could be important for Seattle with Dobbs and Hill out.
Cornerback Marcus Burley is questionable after suffering a minor ankle sprain against the Steelers. Carroll said they believe Burley will be able to play on Sunday.
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