Rashard Mendenhall - What, really? Yes. The 49ers haven't been very good at stopping inside rushes, one area where the Cardinals have shown a lot of trust in Mendenhall. In addition, he looked a little healthier last week against Carolina. He'll never be an RB1 but this isn't a bad week to play him as a flex if you need him. However, if Patrick Willis is finally healthy enough to play, you won't be blamed for sending Mendenhall straight to the bench.
Vernon Davis - The Cardinals have struggled covering tight ends this season, and against Carolina they decided not to bother at all, instead shutting down the run while leaving Greg Olsen wide open more than a couple times. Though Davis would appreciate the gesture, he's not the kind of weapon that needs receiving yards handed to him like buttons at a political rally. He has accounted for four of the 49ers' six passing touchdowns and will look to add to that total on Sunday.
Wide receivers - Are the 49ers good at defending the pass or are they just easy to run on? The result is the same for fantasy owners: teams that don't have Aaron Rodgers at QB are struggling to break 200 yards passing against the 49ers. Sadly, the Cardinals do not have Aaron Rodgers at QB. Larry Fitzgerald, dealing with multiple hamstring issues, may not play. This could mean more targets for Michael Floyd and Andre Roberts, but probably just means that a sub-par passing offense will be even worse than normal. On the other side, the 49ers have already given up on the idea of completing passes, so don't expect much, not even from Anquan Boldin.
Inside linebackers - This game boasts four of the best inside linebackers in football. Karlos Dansby, Daryl Washington and NaVorro Bowman have all been playing great football and it has translated to fantasy points. Patrick Willis may be returning to the field this week, which will be a treat for fans of good defenses and fantasy owners everywhere.
49ers Defense - Until Carson Palmer returns to the starting line-up in favor of the turnover machine that just so happens to look at lot like him and wear the same jersey, the Cardinals offense is going to be a favorable match-up against fantasy defenses.
Cardinals Defense - The 49ers have been utilizing a very conservative gameplan this season, looking to their running backs to provide most of their offense. That's going to limit sacks and interceptions, two important fantasy statistics.
Patrick Peterson - The 49ers aren't throwing it much, which means the Cardinals' secondary won't have many opportunities to make plays. Peterson should be covering Anquan Boldin most of the day, which isn't a bad match-up, but as most fans of the Cardinals should know, Boldin's going to find a way to get open at least a couple times regardless of who's on him.