Both cornerbacks have to be fast; lightening fast in fact. They’re the kind of player who you won’t really see for a lot of the game but then suddenly they’ll come up with a massive game-changing play. It is is their job to intercept or at least interfere with a quarterback’s pass before it is caught by the wide receiver. Because the majority of quarterback’s passes are not intercepted, being a cornerback is a bit of a fishing exercise.
They do block and tackle but because they’re more about pace, they don’t tend to tackle very hard. So this is why they’ll do their damnedest to get a hold of the ball. Catching it is another matter entirely though. It is so often the case that a cornerback reads the pass, gets into position and then drops the ball. This is of course a better play than letting the opposition catch the ball, but it can be frustrating to miss out on a turnover in this way.
There are a few different standard methods of cornerback coverage. “Help over the top” is where they team up with a safety in order to try and put a receiver out of the game. This is often reserved for the very best receivers.
“Bump and run” is where the cornerback aims to disrupt the timing of the opposition runner. They react as soon as the play starts and do what they can to block the wide receiver at the line of scrimmage. If they get in their way for just a short time, there’s a high chance that even if the receiver breaks free of the line and goes downfield, they will be too late to receive the pass from the quarterback.
“Man coverage” is where the cornerback sticks to the opposing receiver like glue and does what he can to force the receiver towards the touchline so they are more likely to go out of bounds if they receive the ball.
“Zone coverage” is where the cornerback covers an area of the pitch and only tracks a man if he is in that area, as opposed to following that man around everywhere on their route. This type of coverage can be good for interceptions, because the cornerback is spending more time watching the quarterback, so has a better chance of reading their pass.