ALLEN PARK, Mich. -- On Oct. 21, 2006, in a nationally televised game with ESPN's "College GameDay" on site, the Clemson Tigers pulled off a feat most thought was impossible, and one that hasn't been replicated since. They shut out Calvin Johnson.
When former Tigers coach Tommy Bowden was interviewing Vic Koenning to become his defensive coordinator after the 2004 season, part of the interview, Koenning said, focused on the plan he had to double-team wide receivers. The main concern was Johnson, a rising star at Georgia Tech.
To account for Johnson, Koenning developed what he called a "Cover 21," in reference to Johnson's jersey number. Koenning devised this plan before the Tigers' 2005 game at Georgia Tech, when Johnson was limited to four catches for 46 yards. Koenning used the tape of that game, which Clemson lost 10-9, to tweak his creation.
It set up the next season's matchup, the only time in Johnson's pro or college careers he has been held without a catch.
So how did Koenning and Clemson do it?
"It is not as complicated as what you may think," Koenning said. "Those [zone] coverages are probably on the 'Madden' football game. By doing it based on where he was, that was the unique part of it."
On likely passing downs, the Tigers often had a linebacker sit underneath in case quarterback Reggie Ball tried to hit Johnson on a short route. As Johnson ran downfield, a cornerback and safety bracketed Johnson to keep him from breaking free for big plays.
The scheme began as a variation of a basketball box-and-one with a hybrid of man and zone coverage essentially boxing Johnson in. This disrupted Ball, who targeted Johnson just three times.
The way Koenning deployed his linebackers, sitting them underneath to cut off short and intermediate routes, came from his first boss in college football, Charlie Bailey at Memphis State, who employed a two-deep zone with linebackers cutting off shorter routes.
If Johnson lined up outside, Clemson "did a strong rotation" toward Johnson. The cornerback assigned to Johnson mixed press and off coverage depending on the play in an attempt to confuse Johnson and Ball.
If Johnson switched sides, defenders remained in their spots, but Clemson flipped the coverage. If Johnson moved inside, the Tigers rotated the safety into the box and tried to jam Johnson.
Clemson also kept the 5-foot-11 Ball hemmed into the pocket during pass-rush situations, limiting his ability to see shorter routes over the middle. Koenning mandated that everything had to go outside -- eliminating one-third of the field.
"It was a tough game," Johnson said. "I don't remember who I was going up against or anything like that. They didn't switch guys, but they had a couple of good guys. A couple guys that played in the [NFL] on that secondary."
Koenning could afford to take chances with his back seven because of the confidence he had in his defensive front, which included future NFL draft picks Phillip Merling, Darell Scott and the late Gaines Adams. The combination of an unspectacular quarterback in Ball and a dominant defensive line allowed Clemson to successfully use this strategy, and it's part of the reason why future defenses couldn't duplicate Koenning's success. In the NFL, the Detroit Lions' other offensive weapons would make this type of defense extremely risky.
Plus, Clemson made it the focus of its entire week of practice.
"We were confident in it," said Houston Texans safety Chris Clemons, a sophomore on that Clemson team. "We talked about it all week, especially the secondary and linebackers. We all [were] hyped. We all were talking about it."
Johnson's only touch came on a rushing attempt when he lined up in the backfield. Ball pitched the ball to him on an option on the left side, but Clemson had the play covered. Johnson ran over Tigers cornerback C.J. Gaddis but still was tackled for a 4-yard loss. Clemson went on to win 31-7.
The Tigers defense wasn't perfect -- Clemons was flagged for pass interference against Johnson on Georgia Tech's first offensive play, for instance -- but it was effective enough to fluster a Yellow Jackets offense accustomed to seeing opponents focus on Johnson.
For one game, though, Clemson made Johnson a nonfactor.
"They doubled him up and wouldn't let him catch it," said Chan Gailey, Georgia Tech's head coach from 2002-07. "They tried to jam him at the line. They did the best job of anybody.
"People tried to copy it, but we got better at moving him around and doing some different things after that game. They were they only ones who really did anything major against him."