I don’t know who started this thing about “gap and zone” but repeating it just makes people look silly. No one only runs “zone” or only runs “gap”. They might favor one or the other but you’re not going to run only one. It would limit the playbook.
Well, you might want to tell 7 NFL teams that who ran it only 80% of the time in 2020. So while true they didn't run only one - they heavily favored one or the other. And some of them BTW have traditionally had the best rushing offenses in the NFL - Titans, Cowboys, Packers, Rams. Now there are also the Jets, Vikings and bears.
So perhaps I didn't clarify.... I'd like to see more of a Titans, Cowboys, Packers, Rams approach. Run one 80% of the time. Because despite what people think there is a very clear difference, from coaching to implementation. I think for the OL to take the next step, becoming either a primary ( not solely for clarification purposes) gap or zone team would be beneficial.
Zone blocking vs. Gap blocking
Beyond the actual coaching points for each individual concept, there’s a couple of fundamental differences between gap and zone blocking that are worth closing with.
First and foremost is how the concepts work philosophically. Zone runs work around the idea that the back will be like water, finding a hole where the defense isn’t. Gap runs have a hole in mind before the ball is snapped and depends on the offense imposing their design upon the defense.
The second difference is how each scheme creates leverage on a defender. Zone asks the blockers to step in unison and work in tandem to overtake and wall off defenders while each lineman runs along their track. Gap asks lineman to block down the line of scrimmage from their initial starting spot and away from the hole, as this creates an advantage from the jump.
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