C.J. Spiller's effect on Fred Jackson

Throughout the preseason, "Decisions 2012" will give ESPN Fantasy writers an opportunity to address some of the key questions and storylines facing fantasy owners as they prepare for their drafts.

Will C.J. Spiller's emergence in December crush Fred Jackson's fantasy value in 2012?

Fred Jackson was on his way to a top-five RB fantasy season in 2011 before a broken right fibula ended his campaign in Week 11. To that point, his backup C.J. Spiller had mustered 3.1 offensive touches per game, thus offering absolutely no threat of a backfield platoon. Meanwhile, Jackson had averaged 93.4 rushing yards per game -- third in the NFL -- and had surpassed 40 yards receiving in half of his starts. He had, in fact, proven an exception to the rule that rushers who've reached age 30 can't succeed, but an asterisk must be attached to that note, because Jackson played two years in the Arena Football League and one in NFL Europe, and thus has less NFL-level wear-and-tear than most backs his age.

But once Jackson was injured, Spiller took over, and particularly in the fantasy playoffs earned a lot of friends. He scored a TD in four of six weeks and averaged 18.3 touches per game; in the final three contests of 2011, he scored 28, 19 and 16 fantasy points. On tape, we can finally see what the Buffalo Bills saw when they drafted him No. 9 overall in 2010: a quick perimeter player with breakaway speed. Now entering 2012, the question is how will the workload break down in the Bills' backfield?

Despite his age (now he's 31), I still prefer Jackson. He's a more complete player than Spiller has shown to be at this point in their respective careers, and at 6-foot-1, 215 pounds -- compared to Spiller's 5-11, 197 pounds -- Jackson is somewhat more suited for interior carries.

I think you see this partway proven by the fact that while Jackson was healthy last year, Spiller lined up a bunch at wide receiver. But the numbers also show a bias: According to Stats, LLC, 63 percent of Jackson's carries qualified either as "middle," "left" or "right" (as opposed to "left sideline" or "right sideline"), while for Spiller that number was 56 percent.

Each man catches it very well, and Spiller probably is more likely to take a long one to the house. But despite Jackson's disappointing broken leg in '11, I don't think it's fair to say that Spiller is a safer health bet. After all, part of the reason he wasn't used much to start the 2011 season was a balky knee. He had hamstring problems in his rookie season, and his time at Clemson also was marked by leg injuries.

This winter, the Bills scrapped the final year of Jackson's contract, essentially giving him a $3 million bonus. That's a nice gesture, but it's hardly a cap-altering deal, and gives the team flexibility to change its mind if Spiller's arrow continues to point way up; it won't cost the Bills any additional dollars to cut Jackson before the '13 or '14 portions of his new contract kick in.

And that makes sense, because in his limited action last season, Spiller did prove a devastating player in the open field. In that regard, he's simply too good not to use a bunch. You'll see some two-back sets this season, with one or both guys sent into pass patterns. Spiller, in particular, is a tough matchup as a receiver, because he's too fast for most one-on-one coverage. But Jackson's ability to make uncannily excellent split-second decisions in the box sets him apart. Spiller doesn't have that in his game yet. He didn't set up blocks as well in 2011, and was caught running backward on a few occasions late in the year.

Expecting Jackson to resume a top-five pace in 2012 is folly. Spiller finally proved in December of his second pro season that he "gets" the NFL game, and as such we're headed for some form of platoon in Buffalo. There will be weeks where Spiller's box score line looks heartier than Jackson's, especially weeks when the Bills fall behind, because Spiller can still split out wide and get looks as a nasty fourth receiver.

But if I'm taking bets on which guy is going to lead the team in rushing TDs, rushing carries and rushing yards, it's still the workmanlike, dangerous, instinctive, bigger Jackson. In my new ranks, I've got Jackson listed as my No. 15 RB (and No. 35 overall), while Spiller is listed as my No. 27 RB (and No. 65 overall).