They aren't selling this like it's a big issue. So I assume a sprain? 2-4 weeks?
Either way, this at least opens the door for Dunbar or maybe even Davis.
Only thing I would worry about is how those guys would respond to in game action at this point after not being in it all season. Makes me worry about fumbling. That said, they're pros, they should able to handle it.
Gurley's growth into a 3 down back and the use of Tavon has really mostly limited Brown to late game clean up duty anyway.
Not great, but not a back breaker by any means. Got some guys who should be able to step up anyway.