"The most demoralizing thing for a defense is when you have a team stopped in coverage, and the quarterback scrambles for a first down," Campo says.
So simply playing good defense against a mobile quarterback isn't enough. That's where the spy comes in.
The Bears often utilized a spy, sometimes middle linebacker
Brian Urlacher, against a host of fleet quarterbacks en route to a division title in 2001. The Redskins neutralized McNabb in a 13-3 victory over the Eagles in week 11 by deploying linebacker
LaVar Arrington. The Patriots annually shadowed Flutie, first in Buffalo and later in San Diego.
"[Patriots coach Bill] Belichick usually likes to get a spy guy on me and put him in the middle," Flutie says.
Flutie knows it's coming, not only against the Patriots, but at some point in the game against most opponents. So while it's called the spy, the defense hardly is covert.