AP

Say what you will for Rex Ryan, but you’ve never been able to say he doesn’t know how to coach an NFL defense. At least not until this year.

This year, Ryan’s first season as head coach of the Bills, his defense has taken an enormous step backward. And in a season when Bills quarterback Tyrod Taylor has emerged as one of the pleasant surprises in the NFL, Ryan’s defense is the reason the Bills won’t make the playoffs.

When you look at the statistics, it’s stunning how much worse the defense Ryan coaches this year is than the defense he inherited from last year:

This year the Bills have already allowed 301 points in 13 games. Last year the Bills allowed 289 points in 16 games.

This year the Bills rank 20th in the NFL in yards allowed per game, allowing 358.8. Last year the Bills ranked fourth in the NFL in yards allowed per game, at 312.2.

This year the Bills rank 17th in the NFL in yards allowed per play, at 5.5. Last year the Bills ranked third in the NFL in yards allowed per play, at 4.9.

This year the Bills rank 17th in the NFL in third-down conversion percentage, allowing first downs on 39 percent of third-down plays. Last year the Bills ranked first in the NFL in third-down conversion percentage, allowing first downs on 33 percent of third-down plays.

This year the Bills rank 10th in the NFL in defensive passer rating, allowing opposing quarterbacks an average rating of 84.0. Last year the Bills ranked second in the NFL in defensive passer rating, allowing opposing quarterbacks an average rating of 74.5.

This year the Bills rank 30th in the NFL with 19 sacks. Last year the Bills ranked first in the NFL with 54 sacks.

This year the Bills rank 26th in the NFL in allowing long passing plays, giving up 49 passes of 20 yards or longer. Last year the Bills ranked second in the NFL in allowing long passing plays, giving up 36 passes of 20 yards or longer.

We could go on all day with stats like this: Across the board, the Bills’ defense is worse with Ryan than it was before Ryan arrived. Add in the fact that the Jets’ defense has gotten better this season under Todd Bowles than it was last season with Ryan, and the conclusion is clear: Ryan isn’t quite the defensive genius he’s made out to be.