Clinton Portis 50/50 for the Dallas game, injury updates

[htownskinfan]

I'd like to know when this injury occurred? I've been pretty happy with zorn but he blew it last week,I was screaming bloody murder at him at the end of the game last week,there was no reason for the starters to still be in there with 3 minutes left trying to score a meaningless td,there was a play in the last 3 minutes where Portis was tackled on the sideline,looked kind of like a horsecollar tackle and he got bent back very awkwardly and i thought for sure he was hurt,I'd bet it happened on that play.
If Alexander is our starter our def better come up big,I'd rather have Sellars start than Alexander