I've been dealing with this lately too. My first reaction was to start blitzing my corners, but somehow, they always end up burning me on one play. The best way I have found to stop people doing this s*** is as follows:
Nickel 3-3 Package.
Man coverage with safties in deep coverage.
I drop my linebackers into coverage so that I have man coverage on the outside WR's.
Most people roll and throw to the right hand side during this crap, so I cheat my secondary to the right of the field.
I put my LE (from the offense's POV) into contain and my RE to cover the flat.
I usually use my left linebacker to cover the left side of the field to make sure they don't roll out that way. Once they start moving outside the pocket, I will bring pressure on the QB from the closest player and force him to throw.
I have tried a ton of stuff and this has worked the best. I'm not a great player or anything, but I think I have this one covered. I get so mad when people do this all game. Now, I love when they quit after they go 4 & out two or three times.
Hope we can stop this crap...