Detroit opens its season missing the two guys who were supposed to anchor the back end. Brian Branch and Kerby Joseph, the Lions' starting safety duo, are both out for the opener against New Orleans. That is not a rotational piece missing. That is the whole safety room.
The Lions built a defense last year that could hang around the ball and clean up mistakes. Take away both safeties in Week 1 and you are asking backups to learn on the job against a Saints offense that would love nothing more than an open lane over the middle. New Orleans did not ask for this favor, but they will take it.
Detroit is still Detroit. A depleted secondary does not undo a roster built to win a lot of football games. But secondaries are where opening weeks get decided, and the Lions are starting this one down two starters at the position most likely to get tested early. Saints or Lions, Week 1 style.