What most teams do to combat the blitz is to go to their "hot" receiver, but there is a big danger in dong that against a good "zone-blitz" team like the Packers because they know how to make the slant very difficult. What zone-blitz teams do is send a defender such as a defensive back that is lined up extra wide and then as he is coming, drop back the defensive end into the slant zone area. And keep in mind that the quarterback is taught to throw the ball into the area that the blitzer just vacated and that plays into the hands of the zone-blitz team. For more on the zone-blitz see this fine article by Danny Kelly from the Seattle Seahawks SB Nation site FieldGulls.
So, what can the Cowboys do to be safe in their hot receiver? The best way is to throw to a hot-receiver on the other side, or to go to a wheel route by the running back, or to have the receiver on the other side of the blitz to pull up for a bubble screen.
I have been dying all year to point out how much I wish the Cowboys would use a "we didn't see that coming" play and now seems like the time to mention it because now is the time it may be needed most. A play in the playbook that they have not used all year and the defense would not be prepared for. These are best when they are what some call "trick" plays. A good example would be the one the Patriots used yesterday where it looked like a bubble screen to Julian Edleman, but what it turned out to be was a backward lateral to Edleman who then threw a 51-yard TD pass to a wide open Danny Amendola. Here is the play.
Games are often won by a couple of big splash plays and no one knew this more than Tom Landry who had at least one trick play ready for every game, and he would use it at the most opportune time.
I would sure love to see the Cowboys burn the Packers on their blitzes, and run some "we didn't see that coming" plays such as the shovel-pass to Witten...watch here. The Packers will be ready for this one, but who knows, maybe the Cowboys have something else ready for them?