St. Louis Rams running back Zac Stacy has been a fantasy football revelation since taking over the starting job several weeks ago, but due to the combination of a tough matchup and a lingering injury, the impressive rookie will fall flat in Week 13.
RBs Knowshon Moreno (ankle), Ryan Mathews (hamstring), Zac Stacy (concussion) and Chris Ivory (ankle) all are expected to play today.— Adam Schefter (@AdamSchefter) December 1, 2013
While Stacy's fantasy owners have to be relieved by that news, it doesn't mean that a strong showing is automatic. Stacy has been remarkably consistent since surpassing Daryl Richardson and Isaiah Pead on St. Louis' depth chart in Week 5; however, running room will be hard to come by against the Niners.
Although San Francisco isn't as dominant against the run as it has been in past years, facing the Niners' defense is no picnic for opposing running backs. The 49ers are surrendering roughly 105 rushing yards per game and have given up nine rushing scores, but teams are averaging just 3.9 yards per carry against them.
What is Zac Stacy's fantasy ceiling in Week 13?
To Stacy's credit, he has at least 78 rushing yards or a touchdown in every start this season, so he has been money in the bank for his fantasy owners. That doesn't mean that it has always been smooth sailing for him, though. When Stacy went up against the Carolina Panthers' impenetrable run defense in Week 7, he gained just 53 yards on 17 carries, but his day was saved by a receiving touchdown.
Stacy has been an inconsistent pass-catcher since becoming the starter, so while he could potentially do some damage in that regard, it wouldn't be wise to rely upon him to do so.
In addition to the difficult matchup, Stacy's concussion has to be considered. The fact that he has been cleared to play means that the Rams' medical staff is confident he is fully healed, but concussions are tricky, especially for a tough-running ball-carrier such as Stacy.
The 49ers boast one of the NFL's most physical defenses, and they are going to punish Stacy every chance they get. It's impossible to predict injuries, but the Niners may present the worst possible matchup in terms of avoiding another injury as far as Stacy is concerned.
It's also important to note that Stacy has some company in the St. Louis backfield. Fellow rookie Benny Cunningham was impressive in Stacy's absence last week as he gained 109 yards on 13 carries and scored his first career touchdown. Stacy is the bell-cow back when healthy; however, head coach Jeff Fisher may be compelled to spread out the carries more judiciously this week with Stacy coming off a concussion and Cunningham showing well.
That, in and of itself, could limit Stacy's potential in Week 13. Stacy will have an opportunity to take that factor out of the equation if he excels early in the game, but it's difficult to imagine Stacy gashing the 49ers' front seven.
Stacy's supporters will point to the 134-yard effort he produced against the Seattle Seahawks in Week 8, but it has been proven this season that the Seahawks can be run on a little bit. Also, that game represented backup quarterback Kellen Clemens' first start of the season, so the game plan was far more conservative than it has been ever since.
Suggesting that Stacy shouldn't be in your fantasy lineup this week may be a difficult sell as far as his owners are concerned, but it isn't an outrageous suggestion by any means. Week 13 is huge for many fantasy owners since it is the final week of the regular season in a large percentage of leagues. For owners needing a win in order to make the playoffs, they can't afford a poor performance.
Stacy certainly isn't an RB1 or RB2 this week, and even playing him at flex is risky. If you have other desirable options, don't hesitate to leave Stacy on your bench. Otherwise, plug him in at flex and hope that he saves his day with a short touchdown run, because he simply isn't likely to rack up yardage against the Niners.
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