Agile and quick, the two cornerbacks are the pass coverage gurus on the defensive football team. Great cornerbacks have great instincts for the game of football, specifically how to cover, read, adjust, and break on the ball. They are the anchors of the pass defense, and their effectiveness greatly influences the success of the overall defense.
What Does a Cornerback Do?
As with all football positions, the cornerback's assignments vary depending on the play called, and the defensive scheme. Here are a few basic techniques that cornerbacks will implement.
In press coverage, a corner will line up close to his receiver, and try to get a jam on the line of scrimmage to slow the receiver's route. Once the jam is made, the corner will drop to his zone, as in cover 2. Jamming a receiver is extremely difficult to do well and legally. If the ball is thrown quickly, it's easy to pick up a pass interference call in press coverage. But corners that jam well save their safeties and linebackers a lot of pain by giving them time to get in position, not to mention the disruption of the receiver's route.
Man-to-man coverage is arguably the most difficult technique to do successfully on the football field, and corners play man-to-man more than anyone else. It's often said that the cornerbacks are "on an island" with their receiver, because wherever the widest receiver lines up is where the corner usually lines up. The wide receiver always has the advantage, because he gets to make the first move, and he knows where the ball is headed. Man-to-man is easy to understand, but hard to do well; find your man, cover your man, don't let him catch the ball.
Many times, a corner will disguise press coverage (what this means), and then bail into their deep zone, as in cover 3 when the ball is snapped, or immediately before. The ability to get deep quickly is an important aspect of this technique.
What Makes a Good Cornerback?
Regardless of the technique, a good cornerback understands the passing game, and the timing of receivers. He has great footwork, quickness, speed, and football instincts. This type of skill set is difficult to find in a taller athlete, so most corners are shorter than the rest of the players on the field. Moreover, he will need to be able to tackle and be physical. Because of the inherent advantage that a receiver has, many defensive schemes assume that short passes will be caught and that the defensive back will be able to make the tackle without many yards after the catch.
Two good cornerbacks are a great commodity for your football team. If you have them, you will be able to create a lot more problems for an offense with your linebackers and defensive line.