The Patriots have no linebackers
To blame the injury bug is a bit cliché, but that's exactly why the Seahawks have an advantage against the Patriots. With Adalius Thomas out of the year joining Eric Alexander, Shawn Crable and Bo Ruud, the Pats have ho healthy bodies left. New England will be without Pierre Woods who reportedly has a broken jaw. Also, Vince Redd is sidelined with an ankle injury. The Seahawks have speed, and spreading out the defense will take advantage of the matchups, going against older linebacker in Mike Vrabel, Rosevelt Colvin and Tedy Bruschi.
Defensive line can't get pressure without Warren
The Pittsburgh Steelers offensive line has given up sacks at an amazing rate over the season, but the Patriots were unable to generate much of a pass rush on their own. Part of the problem - a big part - is the absence of Ty Warren who is nursing a groin injury. Warren would typically collapse the pocket on one side while Richard Seymour did the same on the opposite side. Without Warren, Mike Wright and Jarvis Green have
Home Crowd Advantage
Qwest Field is known for giving the Seahawks a significant homefield advantage due to crowd noise. While all stadiums can be loud, Quest's architecture -- overhangs on both sides - has the effect of bottling in the sounds so the noise level on the field is increased. If the Patriots can't take the Seahawks out of the game early, crowd noise will come in to play forcing false starts and other missteps.
Seneca Wallace is Not Matt Hasselbeck
One of the biggest factors facing England is the mobility of Seneca Wallace. Matt Hasselbeck was ruled out of Sunday's game due to injury, so Wallace gets the start. While Wallace has had trouble throwing, he can go Wildcat on New England in passing situations, likely finding big running lanes depending on how the defense is playing the pass.
Third down defense
The New England Patriots defense is absolutely horrible on third down. It allowed a woeful 50% success rate last week against the Steelers and is one of the worst in the league (bottom three 45% ) If they struggle in Seattle, The Seahawks will find a way to make them pay.