Niners receiver Michael Crabtree makes a three-yard touchdown catch around cornerback Patrick Peterson Monday night.
The Cardinals built their early-season success in part on the way they defended their goal line.
Protection of the red zone hasn't been as effective of late, and heading into Sunday's game against the incredibly red-zone efficient Green Bay Packers, the Cards know they need to change.
"As a defense we have to just try to turn it up another notch," defensive end Calais Campbell said. "Giving up touchdowns doesn't win games. We know the difference. If we hold teams to field goals, we win. If we give teams touchdowns, we lose."
The Cardinals' defense allowed just three touchdowns and six field goals through the first four games of the season. In the last four, the Cards have surrendered seven touchdowns and just one field goal in the red zone.
Statistics support Campbell's theory. While starting the season 4-0, the Cards gave up six fields to three touchdowns. In the last four, all losses, they gave up one field goal to seven touchdowns.
Meanwhile, Packers quarterback Aaron Rodgers has led the Packers to the second-best red zone offense in the league, scoring on 72 percent of their trips inside the 20-yard-line. The Packers have scored 18 touchdowns in 25 tries in 2012, and the Cardinals have given up 10 touchdowns in 21 visits to the red zone.
The Cardinals are still 12th in the NFL in red zone defense (47.6 percent). But the solution won't be found in changing the Cardinals' scheme, defensive coordinator Ray Horton said.
"Tackling," Horton said. "It's just we have to make a play that's presented in front of us."
Most likely those plays will be against passes. The Packers notoriously like to throw in the red zone, opting for the air more over the ground in every down-and-distance scenario inside the 20 this season except one – they've ran and thrown equally on first-and-1 in the red zone.
The Cardinals spent more time than usual this week practicing their tackling and it comes when the Packers are finding a rhythm in the red zone, going 10-for-13 in their last four. By comparison, the Cardinals' defense prevented a red-zone touchdown in just two of their last nine attempts.
"We actually talked about that in the meeting (Wednesday)," safety Kerry Rhodes said. "We've got to get back to doing better.
"It's going to be on the defensive backs and we got to make some stops and play better with our technique and just do what we did in the first four."
RODGERS KEEPING TABS ON LENON
Their careers overlapped just one season, but Rodgers has kept tabs on Cardinals linebacker and former Packer Paris Lenon. The two shared a locker room in 2005, Rodgers' rookie season, and Rodgers remembers Lenon leaner back then.
"He looks pretty cut up and built right now," Rodgers said. "It's impressive what he's done to his body, but he was always very athletic, fast.
"I give him a lot of credit. If you look around roster across the league there's not a lot of guys playing 10-plus years, especially not a linebacker so he's obviously done the right thing off the field keeping his body in shape. On the field he has to have that level of preparation that keeps a guy around and I give him a lot of credit and I'm happy for him."
Only two Cardinals won't suit up Sunday in Green Bay. Guard Adam Snyder is out for a second straight week with a quad contusion and quarterback Kevin Kolb won't dress.
TE Todd Heap (knee), S Kerry Rhodes (back) and CB Greg Toler (hamstring) are questionable.
T D'Anthony Batiste (toe), DT Darnell Dockett (hamstring), TE Jim Dray (knee), CB Jamell Fleming (back), LS Mike Leach (back), FB Anthony Sherman (knee) are probable.
The Packers will be without three starters. LB Nick Perry (knee/wrist), FB John Kuhn (hamstring), CB Sam Shields (ankle) are out, as is backup DE Jerel Worthy (concussion). WR Greg Jennings and DB Charles Woodson are also out.
WR Jordy Nelson (hamstring) is questionable.