The Lions allowed opponents to complete 68.4 percent of their passes and post a 110.9 combined passer rating last year, worst in the NFL in both categories.
This year, the Lions are allowing opponents to complete 73.3 percent of their passes and post a 119.7 combined passer rating. Again, they're worst in the NFL in both categories.
Consider the NFL records for individual quarterbacks. The highest completion percentage ever in a season was 70.55 (Cincinnati's Ken Anderson in 1982). The highest passer rating ever in a season was 121.1 (Indianapolis' Peyton Manning in 2004).
At least the Lions' defensive backs have intercepted three passes. All of last year, they picked off only one.
The pass rush certainly plays a role. But the Lions have been beaten physically and blown assignments too often on the back end. After Sunday's 28-20 loss to the Steelers, Pittsburgh quarterback Ben Roethlisberger said he hesitated on a touchdown throw. He said he was expecting to see a safety and couldn't believe his receiver was so open.
"They executed, and we didn't," safety Marquand Manuel said. "Championship teams are going to execute. We have to try to get to that level."
But it isn't just pass defense. The secondary has contributed to poor run defense at times, too.
When the Lions faced Minnesota running back Adrian Peterson on Sept. 20, they limited him to 43 yards -- except for two carries when cornerbacks made mistakes. Peterson gained 22 yards after cornerback Phillip Buchanon failed to contain him. He scampered for a 27-yard touchdown after cornerback Anthony Henry missed a tackle.
The Lions have allowed seven runs of 20 yards or more. Only the Texans have allowed more.
"We're going to look at every possibility there, because we need more production out of our secondary with pass defense, but also run defense," coach Jim Schwartz said. "We've given up way too many long runs, and long runs aren't the fault of the front seven. ...
"You shouldn't have longer than 12-yard runs if your secondary's doing a good job. So there's a lot of issues back there, from assignment to tackling to pass defense. We're going to look at all of them."
Nine out of 10 members of their secondary were new when the Lions made their final cuts Sept. 5. The one holdover was safety Kalvin Pearson, who just joined the team last year.
In five games, the Lions have tried four different groups of starters -- partly because of injuries, partly because of poor performance. Buchanon was replaced by Will James in Week 3. Henry was replaced by Buchanon on Sunday.
"We're still going to look at a lot of different things in the secondary," Schwartz said.
- QB Matthew Stafford missed Sunday's game against Pittsburgh with a right knee injury. Coach Jim Schwartz said if Stafford can play Sunday at Green Bay, he will play, even if he's not 100 percent. The Lions will not hold him back just because they have a bye coming up and he could have two weeks off.
- QB Daunte Culpepper had mixed results in a 28-20 loss to the Steelers. He showed his mobility with a 32-yard scramble and threw a 25-yard touchdown that made it a one-possession game in the fourth quarter. But he also held the ball too long and took seven sacks -- six of them on first and second down -- and threw a bad interception.
- TE Brandon Pettigrew was targeted six times against the Steelers, but he caught only three passes for 27 yards. He has been an asset as a blocker, though.
- WR Calvin Johnson has left each of the last two games with injuries. He took a helmet to the thigh Oct. 4 at Chicago, then he suffered a right knee injury Sunday against Pittsburgh. Schwartz said the injury is not significant, but it is unclear whether he will play against the Packers.
- WR Bryant Johnson did not pick up much slack with Calvin Johnson out against the Steelers. He caught only four passes for 35 yards.
- WR Dennis Northcutt was the Lions' leading receiver against the Steelers, making a big impact for the first time in Detroit. He caught five passes for 70 yards, including a 25-yard TD.
- CB Eric King was placed on injured reserve with a significant left shoulder injury suffered Sunday. This is the third straight year he has ended the season on IR.
- LB Ernie Sims played only a handful of snaps against the Steelers because of a shoulder injury. But he said he felt stronger in the weight room Monday and expects to play more Sunday at Green Bay.
- DE Turk McBride started against the Steelers. He had not played since the Lions claimed him off waivers from the Chiefs, who had made him lose about 20 pounds to try to become a 3-4 outside linebacker. He had put on some weight and learned the defense well enough to play.