You SHOULD be concerned. It's been well documented on this board that runningbacks with a history of consecutive 300+ carry seasons are prone to having a down year after such a workload.
Alexander
2003 326 carries
2004 353 carries
Tomlinson
2001 339
2002 372
2003 313
2004 339
This is regardless of age, etc. It has happened to Emmitt Smith and Walter Peyton. It happened to Ricky Williams. It happened to Priest last year. This is why a few of us have been advocating handcuffing Priest this year - to get the combined yardage and mitigate the risk. You notice I didn't list Priest's stats alone. That is because I agree that he is an injury risk and the overall production from the KC backfield cannot be counted upon without handcuffing. Its a unique strategy for a unique situation. But, some people still can't think outside of the box on this board and have to be beat upside the head with results until its too late. The Raiders have a pretty tough run defense. You'll see more games like week 1 out of this offense than what we saw on Sunday night gauranteed.
So, I'd be very concerned with LT (in particular) and Alexander. I wouldn't get rid of them, but I'd stash their backups if you can on your roster. They are quality starters if either guy misses a few games.
I'm actually starting to be LESS concerned by this than previously. I don't think that there is enough data to suggest that RB with <INSERT NUMBER HERE> are really all that more susceptible to injury than other RB.As I have posted or written several times, a lot has to go right for a RB to average 20-25 carries a game. Even a tweaked ankle or hamstring could stop that RB from doing it again.
The real meat of the argument is how likely is someone to get 350 carries (or whatever line in the sand you want to draw it at). The chances are slim, and the smart money would always take the under no matter which back it is.
IMO, RB is the most physical fantasy position there is, and any back could go down for a game or the season on any play. That's why projecting RB much past 300 carries or so gets to be more hopeful than realistic. Yes, some guys will play every week (and lately that's been LT, SA, and Martin). But I would be hesitant to project anyone at that uber workload level.
So to say LT dropped from 372 to 313 carries is a bad thing, 313 carries is still way more than 3/4 of the league's starting RB.
I also am not the biggest fan of handcuffing, as many times the handcuff will not produce anywhere near as good as the stud did. He may do ok to be a decent fill-in, but there is only one LT . . . or SA . . . or whomever. If Alexander went down, I doubt Morris would average 18 ppg. For most backups, we have no idea how well they would do. We could debate this one all day, I suppose. I lot would depend on the size of your roster. If you can stash guys and not care, great. But in leagues with few extra slots, it's tough to have guys that don't play much on your roster.