Moore left Sunday night's game against the Chiefs about halfway through the second quarter, although it remains unclear when he sustained the injury. Before exiting the game, Moore logged two solo tackles and defended a pass. Mike Adams, who started at safety for much of the 2012 season, entered the game in Moore's place and likely will assume the bulk of his role in his absence.
If indeed this is the rotation the Broncos will go with, expect David Bruton to see some significant defensive snaps as well. "Lower leg" is a Belichickian way of labeling it.
We'll keep you updated as information comes out.