His impact on the defense has been significant, starting with this most basic and most important statistic. This season, the Vikings finished fifth in the NFL with a stingy average of 18.9 points allowed.
''I didn't really have any expectations. I mean, we had to teach the whole thing,'' Zimmer said. ''But they caught on fast.''
In fairness to the previous staff under predecessor Leslie Frazier, the roster has been upgraded by the front office since.
Then there's been marked improvement, by players such as cornerback Xavier Rhodes, who has benefited immensely from technique advisement by Zimmer and defensive backs coach Jerry Gray and cut down on his penalties.
Rhodes was among the many standouts on a defense that carried the Vikings to a 20-13 victory over rival Green Bay last weekend to win the NFC North division and set up a wild-card round matchup with the Seattle Seahawks on Sunday.
''Zim's going to be him. He's still going to be the same play caller. He's still going to be the aggressive coach that he is. We appreciate that, you know?'' Rhodes said. ''He's not going to be scared of making those calls.''
The play calling is where Zimmer has made his mark, starting with his signature ''double A-gap'' blitz that brings linebackers Barr and Kendricks up on either side of the center before barreling through the line. They can fake it, too, and only send one. Or put both of them back in coverage. Or send free safety Harrison Smith or Munnerlyn instead.
Here are some examples of Zimmer's effective play calling from Green Bay:
- Early in the second quarter, third-and-8 for the Packers at their 29-yard line, with the game tied at 3.
Smith lined up next to right end Everson Griffen and blitzed unabated into the backfield, forcing Rodgers to step up in the pocket and into traffic. Kendricks hung back in pass coverage, but Barr brought pressure from the ''A gap'' on the right side of the center. With no room to escape, Rodgers was sacked by Smith and tackle Tom Johnson, prompting a punt.
- Late in the second quarter, third-and-4 for the Packers at the Vikings 39, trailing 6-3.
With Hunter at left end, Brian Robison moved to tackle and stood in a two-point stance. Barr, next to Robison, blitzed in the ''B gap'' between the guard and the tackle. Robison dropped back, moved parallel with the line and spied Rodgers to make sure he didn't scramble.
Kendricks sprinted to his right at the snap to pursue tight end Richard Rodgers, who had a three-step head start on his route straight toward the sideline, but was tackled by Kendricks after the catch for a 1-yard loss. Had Kendricks blitzed, Rodgers would've had an easy first down and more.
- Midway through the fourth quarter, third-and-3 for the Packers at the Vikings 18, trailing 20-10.
This time, Barr and Kendricks stayed in the middle of the field, clogging route lanes for Packers receivers. Rodgers didn't have anyone open, forcing him to hold the ball long enough for Griffen to power his way around fill-in left tackle Josh Sitton for a sack that made the Packers settle for a field goal.
To keep the Seahawks at bay, Zimmer will have to keep that up.
''He'll go back to his base defense when he needs to. Some teams won't do that. They'll jump around and do other things. He's committed,'' Seahawks coach Pete Carroll said. ''He has a very in-depth pressure package and background in doing so, a real style about doing that. Other teams have really taken from him.''
NOTES: RB Adrian Peterson (lower back), DT Kenrick Ellis (ankle) and FB Zach Line (illness) did not practice Wednesday, when the Vikings went outside to prepare for what could be a Sunday afternoon with a subzero temperature. ... Joseph participated on a limited basis. ... The Vikings created a roster spot by placing TE Rhett Ellison on injured reserve, after he tore the patellar tendon in his right knee against the Packers. DE B.J. DuBose, a sixth-round draft pick from Louisville, was signed from the practice squad.
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