Safety Earl Thomas has two of his team's three interceptions. Joe Nicholson USA TODAY Sports

The Seattle Seahawks' defense built an intimidating reputation by creating big plays and preventing opponents from doing the same.

Neither of those are happening with any regularity this season, a big reason why the Seahawks have blown fourth-quarter leads in all four of their losses and enter Thursday night's matchup at the San Francisco 49ers plodding along at 2-4.

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"We're not being ourselves," Seattle safety Earl Thomas said. "I think we're distracted in some areas."

During the previous two seasons, according to the Seattle Times, the Seahawks were the best team in the league at yielding pass plays of 20 yards or longer. Seattle permitted 32 such plays last season and 30 in 2013, but have already been burned on 23 occasions through the first six games.

"Maybe some guys were distracted," Seattle defensive end Cliff Avril said. "Two years of going to the Super Bowl, I could see that being a distraction, assuming it's going to happen ... But, hey, we're 2-4 right now, and if you're not worried about that we've got an issue."

The defense has also failed to produce momentum-changing plays. Although the Seahawks have forced six fumbles, they have registered only three interceptions - two coming last weekend - after posting a league-best 28 in 2013.

"We're not getting the turnovers we need right now," Avril said. "That's coming from sack fumbles or interceptions or whatever. We're not getting those. We need to get back to those more than anything."

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