On offense, there are five linemen and a quarterback on every play—with the exception of the Wildcat or derivations of it, which we’ll get to later—leaving five interchangeable offensive pieces. Personnel groups are identified by the number of running backs and tight ends on the field on a given play, in that order. If a team sends out two running backs and one tight end, it’s called 21 personnel. If it sends out one back and two tight ends, it’s 12 personnel. In both cases, there will be two receivers on the field. The first indicator a defense looks for is the personnel package the offense is sending out. It should be the first thing you’re looking for, too. That’s because personnel tips off strategy. If the 22 personnel is on the field—two running backs and two tight ends—it means there’s only one receiver out there. Immediately, you can make an educated guess about what play a coach is likely to call—in this case, probably a run. You can make your prediction even before they break the huddle once you’ve noted who’s in the game.
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A coach’s master playbook can contain about 1,000 plays—pretty much anything he would ever consider calling in a game. Every bomb, blitz, and blocking scheme is in there somewhere, along with every gadget play and goal-line scenario. And every call has its roots somewhere in that all-encompassing bible, which every coach is forever adding to and carrying with him from job to job. The process of paring down that playbook into a single Sunday’s game plan begins pretty much as soon as the previous season ends. Coaching staffs spend most of January (if they’re out of the playoffs) and February going
through some critical self-analysis, evaluating what they did well and what they did poorly during the season that just ended, and starting to decide what they’re going to retain or change for the following year. At the same time, they are preparing for the start of free agency and the upcoming draft. The personnel plan takes shape based on what the coach envisions being able to do in the upcoming season. He’ll want to target players and prospects who will fit what he plans to run. You better believe Brad Childress’ plan for 2009 changed once the possibility of acquiring Brett Favre first became real. Those early decisions are the building blocks of an eventual game plan. As a team’s personnel changes and its personality evolves through free agency and the draft, the overall game plan is steadily refined. Through organized team activities (OTAs) and minicamps, coaches whittle away at their playbook, identifying the plays that best fit the team they’ll have to work with. They try to maximize the strengths they see emerging, eliminate the obvious problem areas, and anticipate the matchups they’ll be facing. Coaching staffs meet after practice every day, debating the pros and cons of every play they can imagine using in a game situation. The accumulation of those plays becomes the playbook for the next season, and by June 15, that actual playbook goes to the printer. A coach is now committed to his philosophy for the year.
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The receivers get their route information from the play call, too. As you can see on the passing tree diagram—first conceived by legendary Chargers coach Don Coryell—every route is also assigned a number. A quarterback will call his receivers’ routes from left to right across the formation. So, a play called “I Weak Right 819” would have the X receiver running an 8 route (a post), the Y receiver—in this formation, the tight end—running a 1 (a quick out), and the Z running a 9 (a fly). If a running back is going to be added into the pattern, that route will be declared verbally instead of numerically. So, to have the fullback release through the line and work opposite his alignment, the call would be “I Weak Right 819 Fullback Opposite.” Throw in a bootleg by the quarterback, and you have “I Weak Right Boot Right 819 Fullback Opposite,” the play diagrammed on page 36.
Kirwan, Pat (2010). Take Your Eye off the Ball (Kindle Locations 674-681). Triumph Books. Kindle Edition.