Curl–Flat

The concept

A curl settling behind the flat defender and a flat route running in front of him. The oldest high-low in football.

The offense1 / 3
The look
A receiver climbing to eight yards and turning back, with a route running to the flat in front of him. The oldest high-low in football, and the one every playbook has a version of.
vs Man2 / 3
The conflict
Two independent covers. The curl has to be beaten at the break point, the flat with leverage and speed.
vs Man3 / 3
The throw
One defender, two routes. Throw the one he did not take, and expect to make that decision at the top of the drop.

Why it works

One defender asked to widen and sink at once
The flat pulls him outside, the curl settles behind him. Both at the same instant is not something a defender can do, and whichever he starts first is the answer.
The window opens late and stays open
A curl comes back toward the quarterback, so the throwing lane keeps growing as the receiver works back. That is a forgiving throw on a timing route.
It converts on early downs without risk
Eight yards, caught facing the quarterback, with an outlet underneath. Nothing about it needs a matchup to be won.

Curling with your back to the sideline
The receiver has to come back toward the ball, not stand and wait. Standing lets the defender close the distance the route just created.
Running the flat route too fast
It has to occupy the flat defender, not run past him. Sprinting straight through the flat takes him nowhere and leaves the curl covered.
Throwing the curl before the break
Anticipation on a curl is how the underneath defender gets a hand on it. The ball goes as the receiver turns, not before.

Open it in the designer, change the routes, save it to your playbook.