AFC West

Vahe Gregorian: Can a Super Bowl defense get even better during a pandemic? 'Spags' is on the case.

KANSAS CITY, Mo. — A year ago at this time, the Chiefs were consumed with converting their Achilles’ heel into an asset. Or at least something more stable than the precarious defense that had become the only unit able to thwart Patrick Mahomes and their offense — the brilliant collaboration that might have been rendered a novelty act without a supporting cast.So the Chiefs overhauled defensive schemes, and they purged personnel to make money and room for the crucial likes of Tyrann Mathieu and Frank Clark. But hiring Steve Spagnuolo as defensive coordinator was about as pivotal as anything in …