I know this play can be a pain in the ass, but the easiest way to defend it is just man up the slot guy or the TE. If you see a set with 3 guys lined up on 1 side, its smart to man up the guy furthest inside. He's usually the person running the unguarded post, but now that you have a man guarding him, it can take away the deep post. Usually a LB guarding him won't do the trick, so I like to use dime and put the nickel back on him just in case.

If Im using the 3-4 that game, I like to use the play double TE. It double guards the slot guy with an LB and a safety and still has a safety playing over the top.