Colin Kaepernick and Bears in single-high

Significant news broke Monday morning as I traveled back to NFC North blog headquarters: The Chicago Bears will face the San Francisco 49ers' backup quarterback, Colin Kaepernick, Monday night. Starter Alex Smith was not cleared to play because of a concussion, according to ESPN's Chris Mortensen.

How will that impact the Bears? For one, Kaepernick is a legitimate running threat who has 177 yards rushing and three touchdowns in limited playing time this season. He has scrambled on an NFL-high 18.4 percent of his dropbacks. But you also wonder how it will impact the Bears' decisions in coverage, which leads me to a really interesting and revealing blog post from our ESPN Stats & Information crew.

Even though we all continue to call them a "Tampa-2" defense, the Bears have actually used a single-high safety on more than half of their snaps this season, according to Dan Riccio's video analysis. Remember, a single-high safety is like having a center fielder in coverage, typically requiring man-to-man defense from cornerbacks, while the other safety prowls the line of scrimmage. It's a preferred look for run defense, and in the Bears' case, you wonder if it is to limit the times middle linebacker Brian Urlacher is asked to cover the deep middle of the field.

On snaps where the Bears are within one score of their opponents, the slant toward single-high is more pronounced: 64 percent, according to Riccio.

What does this mean for Monday night? A single-high safety would presumably give the Bears another player to help defend Kaepernick if he leaves the pocket. It will also take the chance that a quarterback making his first NFL start might not be asked to exploit man-to-man coverage as much as, say, Smith would. Just another level to consider as we're now less than seven hours from kickoff.