Statistically the Mike Martz offense had a heck of a debut, and Jay Cutler had a nice start to the year. His one interception was thrown into triple coverage, and into a deeper zone coverage like ones he'll see all season long. With the Bears now trying to stretch the field more vertically than in years past (a staple of any Air Coryell derived offense), you need to look for defenses to adjust their zones accordingly.
Whatever zone coverages the Bears see this season, they'll see them setting their underneath zone deeper than in years past. The deep part of the zone coverage won't change as whoever is deep is always taught to be deeper than the deepest offensive player. Here is a basic Cover 3, from NFP, the Bears may see this season:
The strong safety will roll up to replace the corner that is going back to cover deep third, and be responsible for the flat/curl zone. The weak-side OLB will take the other flat/curl zone, leaving the MLB and strong-side OLB to the middle of the field looking for hook/curl. This cover 3 gives a 3 deep 4 under look.
The variance the Bears may see in 2010, is the underneath part of the zone will set up shop deeper. They will set the depth of the zone based on the drop of the QB. If Jay Cutler takes a 7 step drop, the four under part of the zone (SS and 3 LBs in this cover 3) will drop until Cutler sets, then they will flatten out and cover their zones. On the pick Cutler threw, the receiver was in front of the deepest defenders, but he was bracketed in front by a deeper than usual underneath zone. It appeared to be triple coverage so Cutler should have checked down, but that's another story.
One thing Martz is trying to do against a zone defense is run his deep dig route (about a 12-15 yard in) and draw the safety up, leaving a one on one look on a streaking receiver (remember Martz wants to stretch a D vertically). If the deep safety fails to bite up, the dig should be open against a normal zone, but if teams are setting their zone depth deeper they take away the dig.
One thing the Bears can do to keep defenses honest in their zones is run long shallow drag routes from their far split receivers. The longer the crossing route, the deeper the underneath zones will set up, and the more open the receiver should be. But, the thing to be wary of against a zone is if the defenders don't set their depth too deep running through a zone is a great way to get a receiver killed (Devin Aromashodu got popped a few times against the Lions). If the zone is at normal depth, the receiver has to settle down in the pocket between defenders.
One other option the receivers have is after showing the dig route, to belly back under the zone coverage. A lot of what the Bears do will be predicated on the look the defense will give them. Having both the QB and WRs on the same page and recognizing the depth the zone sets up is crucial to their passing game.