The Chargers defense in 2019 was a middle of the road unit as a whole while still thriving in one specific area: pass defense.
Even for a group that was missing two of its’ best players in Derwin James and Adrian Phillips, they somehow still managed to finish fifth in passing yards allowed, third in first downs allowed by passing, and tied for eighth in passing touchdowns allowed. They were a bit more pedestrian in run defense, finishing 18th in rushing yards allowed and tied for 21st in rushing scores allowed.
Now, don’t get me wrong, the Chargers had a fairly good defense despite dealing with injuries and the lack of taking the ball away, but there’s still plenty of room for improvement.