For the first six weeks of the season, the Seattle Seahawks run defense was among the best in the NFL.
In the eight games that have followed, the Seahawks have statistically been among the worst.
For one, the Seahawks have played some really good running backs and been hurt by big gains from Adrian Peterson, Frank Gore and Reggie Bush.
But there are some concerns about the Seahawks giving up 5.3 yards per carry over the past eight games, a number that ranks last in the league during that span.
Some of the problems have been with the game plan, with the 49ers getting the best of the Seahawks with trap plays in their first game.
There have also been issues with defenders getting out of gaps and overrunning plays.
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