The official Backbreaker forums have posted a couple of screenshots that confirm 11 vs. 11 gameplay.
"Another reoccuring theme I've spotted has been the constant doubt over whether we will offer 11 vs 11 gameplay. I know that the NM guys have repeatedly said we will but that we've yet to supply evidence proving that. I'd like to stop that argument for good with a couple of images that the guys back in the office have been so kind as to prepare for me. This isn't final, visual treatment will be changed etc etc etc, but I've attached two shots displaying the current view shown when you pull back from the line of scrimmage to display the routes for your chosen play. These are for you... enjoy, but please remember that we are still in development."

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