Cover 3
Three deep defenders split the field into thirds, with four more underneath.
Cover 3 is a zone coverage. The two cornerbacks and the free safety each drop into a deep third of the field, four more defenders cover the short areas underneath, and the other four rush the quarterback.
It's built to stop the big play: nothing should get behind three deep defenders. It also lets a safety rotate down to help against the run, so it holds up against both.
Its classic problem is four verticals, which is the play in the diagram: four receivers going deep against three deep defenders. Step through it to see how the defense is supposed to handle that, and where it breaks.
College and the NFL: the hash marks are much wider in college, so the ball is often snapped close to one sideline. That leaves the cornerback on the wide side of the field with far more ground in his third, and college offenses attack it.
One safety deep in the middle - a single-high look. The corners are 7 yards off, and the strong safety starts deeper than he'll end up.
Read the play step by step
- Before the snap: One safety deep in the middle - a single-high look. The corners are 7 yards off, and the strong safety starts deeper than he'll end up.
- The snap: The corners and the free safety bail into their deep thirds. The strong safety rotates down to the curl/flat, and the linebackers and nickel drop underneath.
- The play develops: Four receivers deep against three deep defenders. The free safety can only help on one seam, so the hook defenders must carry (run with) the seams. Here the linebacker on the right is a step late, and the tight end's seam is open.
How to spot it
- Count the safeties. One deep in the middle, about 12-15 yards off the ball, means a single-high coverage - usually Cover 3 or Cover 1. Two deep safeties rule Cover 3 out, unless one of them rotates down at the snap.
- Look at the corners. In Cover 3 they line up 7-8 yards off and start backpedalling or turning to run at the snap. Corners in press, eyes on their receivers, point to Cover 1 instead.
- Watch the strong safety. In the "sky" version he starts deeper and rotates down toward the line at the snap, into a curl/flat zone.
- After the snap: if both corners run deep with their eyes on the quarterback while the underneath defenders spread across the field, it's Cover 3.
Strengths
- Hard to beat deep. Three defenders share the deep part of the field, so the long ball is covered.
- Good against the run. With a safety rotated down there are eight defenders near the line.
- Simple and flexible. It can be played from any personnel grouping, and blitzes can be built on top of it.
Weaknesses
- Four verticals. Four deep routes against three deep defenders, so the hook defenders have to carry the seams for it to hold.
- The flats. The underneath defenders have a lot of width to cover, so quick throws toward the sideline are often open.
- The holes between levels. Throws that land between the underneath and deep defenders, around 12-18 yards, can find the gaps.
Key terms
Quick quiz
1 / 3How many defenders play deep in Cover 3?