Here is a simple Cover 1 dog from Vic Fangio's 2017-2018 Bears defenses with a rushing LB reading the turn of the protection. Bears are in Nickel personnel.
The Rush:
DE's are wide rushers. Front has a DT in a 3 technique to the side of the RB with a shade DT away. The LB opposite the RB is reading the OG's pass set. If the guard sets inside to the shade DT the LB pressures the B gap. If the guard sets out to the LB in the B gap the LB loops to the opposite A gap to find daylight in the rush.
The Coverage:
Cover 1 man free coverage with the LB to the RB in man coverage on the back.
First example is on 2nd&7
The guard sets out to the pressure LB, the LB wraps to the opposite A gap. The pass set for the Center is very difficult. The LB is able to win vs. the Center on the redirection set. The pressure also creates a 5 vs. 5 pass rush. The DE is able to win his 1 on 1 vs. the OT on the edge.
2nd example is a 1st&20 later in the game with the Bills in obvious pass mode.
3rd example is on 3rd&8
4th example on 3&8
5th example on 4&6
The pressure LB gets the Guard setting wide on the movement pass with the QB getting out of the pocket. The LB doesn't wrap inside and instead works for width to continue pressuring the QB as the launch point changes. Added bonus in coverage is the hover technique of the DB on the TE. When the TE blocks to help secure the edge for the QB sprint out, the DB hovers. Hover is staying over the top of the man responsibility with depth and vision on the man and the QB. This allows the hovering DB to break like a zone dropper would undercutting routes around him and providing help to man coverage defenders. The QB attempts to throw the ball on a lower trajectory with velocity to fit the ball in vs. man coverage. The man coverage throw allows the hover DB to vision and break getting his hands on the ball.
Good stuff as always from Vic Fangio. He has been coaching good defense for a long time. I'm excited to see his defense in Denver this season.