First in order for teams to counter line-shifts without the o-line having to adjust assignments.
Second so that smaller (athletic) line-men can be effective despite size and strength disadvantages.
And to counter increasingly athletic pass-rushers by utilizing more athletic o-linemen.
Today in the NFL the ZBS is catching on with about a dozen of the teams in the league running it.
And it has seen some success:
Mike Shanahan installed it in Denver, and it made an unspectacular Terrell Davis look great. But it is being reported that Josh McDaniels is doing away with the ZBS in Denver.
With the ZBS, the Seahawks were able to make it to the Super Bowl behind the rushing of Shaun Alexander, who at the age of 32 is no longer in the NFL.
And in 2007 Al Davis hired Lane Kiffin, who brought in Tom Cable and the ZBS. With the blocking system the team ranked sixth, 10th, and then 18th in rushing.
Rather than being assigned a defender, o-linemen are assigned an area in the ZBS. And if no one is in the area, the o-linemen continues through the area he is assigned, assists in a double team, and/or continues to the second level to block a line-backer.
In the simplest terms and situations, o-linemen are responsible for a gap directly next to them.
Common rule terminology for an o-linemen in the ZBS is gap-down-on, meaning his first assignment is his gap, his second is a defender head-up on the guy next to him, and the third progression is the defender head up on the o-linemen.
In the rare occasion there isn't a defender in any of those three areas, the o-lineman still fires through his designated area on the way to the line-backers.
For example the center would be responsible for one A-gap, say the A-gap to his left in this ins...
Article Source: Bleacher Report - Oakland Raiders
