Arizona Cardinals defense ranked 20th in NFL by Pro Football Focus

The Arizona Cardinals’ defense surrendered 27 points in the fourth quarter against the Tampa Bay Buccaneers, and Pro Football Focus ranked coordinator James Bettcher’s unit No. 20 out of 32 teams in the NFL.

After star running back David Johnson dislocated his wrist in Week 1, an injury that will keep him out until at least Christmas, some thought the defense would have to win games for Arizona.

But through six weeks in 2017, only the Indianapolis Colts (32.5), the Tennessee Titans (27.3), the New England Patriots (26.5) and the Dallas Cowboys (26.4) have given up more points per game. The Cowboys have played five games and the other two teams have played six.

To partly explain the Cardinals’ defensive lapses, PFF pointed to the loss of a key veteran contributor this past offseason and an unbalanced secondary.

No Calais Campbell has left a significant hole in this Cardinals defense that they have yet to adequately patch. Frostee Rucker leads the defensive linemen in snaps, and has been extremely ineffective. On the back end, as good as Patrick Peterson is, the other starter is Justin Bethel, and the disparity in talent means Bethel has seen more than twice the number of passes come his way than Peterson, and has already surrendered six touchdowns.

Campbell was a force on the defensive line during his time in Arizona. Last season, he registered eight sacks in 16 games.

Without Campbell, the Cardinals have 12 sacks as a team, tied for the ninth-fewest in the league. Meanwhile, Campbell has already matched his sack total from last season in his first season with the Jacksonville Jaguars and his team leads the league with 23 sacks.

In the secondary, Justin Bethel impressed during the preseason. But, he could be replaced in the starting lineup by Tramon Williams. The Cardinals have given up 13 receiving touchdowns, tied for the second most in the league with the Titans.