Our 2nd stop in the position preview series takes us to the RBs, the focal point throughout our site this week.You already know that RBs lead the way in 2017 ADP, but drafters' reactions to last year are also pushing backs further up in rounds 2 and 3. That includes some rookies going higher than might be comfortable.Of course, their high draft positions leave plenty of value targets dropping into the middle rounds. We'll pick out our favorites in that range as well as some later-round sleepers you can stash on any roster.