Changing the Math with Safety Run Pressure & DL Movement

This pressure is from the 2017 UCF defense.

The Rush:
The DL is slanting from a 4i-0-4i alignment away from the edge rushing safety. The box is initially a 6 man box but the blitzing safety changes the math to a 7 man box.

The Coverage:
Cover 1. Although it is possibly an aggressive version of 3 deep 3 under firezone with pressed corners.

Why did it work?

The box picture for the OL pre-snap is a fairly standard 4-2 look with both ILB's in the box.

Play side the OT and OG are fanning out to the Jack and End. Back side the C&OG are zoning to the Will while the back side OT&Y are zoning for the Mike. By the time the Safety rolls down to blitz and the Mike bumps out of the box the OL blocking is declared. The final picture looks more like a 4-3 defense with the Safety & 2 ILB's combined with the slanting DL to space like a 4-3 box. Because of the initial picture the OG is aggressive to the slanting End and quick to travel back inside. The OT sees the blitzing safety and adjusts but the OG is gone leaving the Jack unblocked. 

Even if the zone blocking had stayed intact the play is outnumbered by the defense and the zone would break in a different place.

The 4i on an outside move is a problem for the zone.

Once the back side OT and Y started comboing for the End and Mike the Zone has a challenge. The OT travels back with the End and eventually works to the Mike. In the last diagram shows what if the OL zone blocks the pressure accounting for the blitzer and slanting DL.
OT fanned to the blitzing safety
OG fanned to the Jack 
C/G combo came off to the End & Nose on the slants 
Even if that all happened the zone would still have broken. The zone cannot account for the scraping Will backer when the RB cuts back. The slanting End and Mike do a nice job of building a wall back side to force any cutback into the rush.

Another option would have been for the combo's to remain as originally declared.

The zone is still outnumbered. If the OT & OG travel back with the Jack and End as they slant the Center & Guard combo works to the Nose & scraping will the safety blitzing is unblocked. The two most likely outcomes are the safety makes the play in the backfield or the run cuts into a wall backside. 

Nice run pressure by Coach Chinander and UCF to create a TFL. The usage of the boundary safety in the pressure creates numbers where the offense did not expect them.