A triangle read combines a vertical stretch to defeat Cover 2 with a horizontal stretch to defeat Cover 3, providing options regardless of the defensive coverage (many of these plays will also include crossing routes to defeat man coverage). There are four possible ways to orient a right angle along the axes of a grid (|_, _|, |¯ , ¯|), so there are four possible ways to orient a triangle read. But are all four of these triangles in use in football today? Why or why not?
Triangle 1: Lower Outside Apex
This is the classic triangle read pass, used in plays like Mesh (Air Raid version and Coverdale & Robinson version), Stick, and Double Quick Outs. The receiver in the flat does double duty: he is the low man in the high-low stretch on the cornerback that is a classic way to attack 2-Deep Zone, and he's also the outside man in the inside-out stretch on the outside linebacker or sky safety that is a staple of attacks on 3-Deep.
Mesh, Coverdale and Robinson version
