At 34, middle linebacker Derrick Johnson is coming off his second torn Achilles in three years (one on each side). Ramik Wilson got better filling in for Johnson down the stretch, but even if he can assume more of Johnson's duties (which include taking the running back in man coverage), this position must be addressed. Despite a large, athletic defensive line, the Chiefs have ranked 22nd or worse against the run in five of the last six years. And with no depth at inside 'backer, they often have to play dime (six DBs) with a third safety in the box against three-receiver sets. As the Steelers made clear in their divisional-round win at K.C., this lighter personnel package only exacerbates the Chiefs' run-stopping woes.