It almost looked to me like Lang was pulling and looking for someone outside the LE to block, but then Lacy had to try to turn it inside when the TE let himself get pushed into the backfield. Assuming the play was designed to go outside, if R.Rodgers gets a decent block and if Lacy doesn't get dragged down from behind by Levy (not clear whether he could have avoided him), that could have been a monster gain.
If what you're describing is accurate, that's an awfully dangerous play to be running out of your own endzone. Especially given the struggles R.Rodgers has had with his blocking.
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