Unless you've been lost at sea for a few years, you know that the 49ers defense doesn't allow anyone to run the football against them. They only allowed 77.2 yards per game in 2011 and went 14 games without allowing a rushing touchdown.
Last week vs. Green Bay the 49ers saw a familiar sight: The Packers abandoned the run and tried to throw the ball around the yard. Well, that didn't work out particularly well, either. While they threw for over 300 yards, eight of 11 drives ended in either a punt, turnover on downs, or an interception.
Defensive coordinator Vic Fangio played a lot of coverage, got pressure with limited pass-rushers, and mitigated big plays in the passing game despite facing the NFL's reigning MVP Aaron Rodgers. A huge key to this was being able to stop the run without loading the box with defenders.
Heading into week two against the Detroit Lions the question becomes: Will they try to run the ball against the 49ers, who showed they can stop even the most potent passing attacks?
I think they just might.
While I don't think they'll be successful, I look for Detroit to make a concerted effort to run the ball against the 49ers. If you take away what a team does best (stop the run in this case) the rest of their plan starts to fall apart, too. If the 49ers don't feel confident stopping the run in their sub packages as they did vs. Green Bay, they can't play as much coverage...which opens up plays in the passing game as well.
With the template in place from last week, I'd look for some single-back formations with the Lions either running draws or motioning the tight end back into the formation as a lead blocker. The Packers didn't try to run the ball, even against the 49ers Nickel and Dime packages. The Lions are probably wondering why not.
If Detroit is able to establish any sort of run game, the 49ers will be forced to play closer to the box, opening up the field for Calvin Johnson to get some single coverage on the outside. Even with safety help over the top, a timely run fake can draw players out of position, hanging the CB out to dry alone with Megatron.
It will be interesting to see if the Lions employ this strategy. Fangio has to know it's a distinct possibility. I have little doubt that the defense will be prepared for anything and even a few good runs wont inhibit it's ability to stop Detroit's offense.