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Keeper Question: Jacoby Ellsbury

Not a lot has gone well for the Red Sox in September, that much has been well documented, but someone forgot to tell Jacoby Ellsbury to pack it up. Red Sox hitters are hitting .278/.339/.463 with 32 HR, a quarter of which belong to Ellsbury as part of his .365/.408/.687 line in 125 PAs this month. His line for the season is equally compelling: .322/.377/.554 with 32 HR and 38 SB. Whether he is the AL MVP remains to be seen, but he’s certainly performed like an MVP, keeping the Red Sox afloat despite the pitching staff’s best efforts to the contrary.

There’s not an owner out there ruing having Ellsbury — John Henry included — so It may seem like a no-brainer to keep Ellsbury, especially given his nearly double-digit WAR. But just like his lost 2010 season didn’t do much to influence his 2011 campaign, 2012 isn’t 2011. Having a realistic sense of how much of his value he’ll keep is the key to making a sober keeper decision.

One factor will change this analysis right from the top, and that’s whether your league uses an articulated outfield or whether you just need to fill 3-5 general OF spots. If you need a CF instead of just an OF, Ellsbury enjoys a nice boost to his value, as his competition at that spot is much less compelling than if RF and LF are included.

Looking solely at Ellsbury’s WAR is going to artificially inflate his fantasy value as his 16.8 runs saved on defense is virtually irrelevant in this context; it matters more when evaluating a Red Sox pitcher than it does for Ellsbury himself. Instead, looking at wOBA is going to give us a pretty good sense of how he’s contributing in the offensive categories most leagues care about. He doesn’t suffer much for the switch, as his .403 wOBA means that he remains a top-10 player, but it does position him more accurately as one of best players this season rather than the prohibitive leader.

The two parts of Ellsbury’s game that I see being the least likely to spontaneously regress are his base-stealing and his batting average. At some point, his speed will start to fade, but age-28 seems awfully early. How much he runs will depend a little on how the Red Sox choose to set up their batting order, but I don’t see much chance that he both stays healthy and doesn’t steal 30 bases. His speed is also an asset in terms of batting average, which has been stably high for almost his entire career — injury vacated 2010 notwithstanding.

What determines Ellsbury’s 2012 draft position and what will make a big impact in any keeper decision is whether or not you think his power — or at least some part of it — will stick around for another season.

The player that just keeps coming to mind as a comparison for Ellsbury’s spontaneous display of concentrated aggression is Joe Mauer. Mauer’s 28 home runs in 2009 seemed to indicate that the power you’d expect from a player of his size was finally showing up and it certainly influenced not only his fantasy values, but also his massive new contract. Two years later, Mauer has hit less than half of that 2009 total with just 12 home runs total since the start of the 2010 season. I’m not necessarily suggesting that Ellsbury is going to lose most of next season to bilateral leg weakness, but the sense that we’ve probably seen his peak value this season is right.

Like Mauer, Ellsbury saw his HR/FB take a huge leap this season, though his rose about 7 percent, where Mauer’s jumped over 10 percent from his career norm. Just because it’s a comparatively smaller leap doesn’t make Ellsbury’s any more sustainable per se, but it means that if he regresses to his career norms again next year, the drop won’t be quite so drastic.

30 HR power has never been part of the scouting report on Ellsbury, and while scouting reports aren’t gospel, there aren’t many guys who make the leap from “average to good gap power” to “potential cleanup hitter” and can make the change stick. If he hits 15 home runs next year, it would still be his second best season ever and yet less than half his total from this year. The question you need to ask yourself as an owner is whether that potential drop of 15-20 HR is a deal-breaker for you.

To me, unless you’re burdened with an outfield of Ellsbury, Matt Kemp, and Jose Bautista with just three spots to fill and no UTL, Ellsbury is going to bring enough to the table to be worth keeping. He’s going to give you solid SB and AVG numbers, and will be driven in a fair amount by the rest of the Red Sox’s order, which gives him at least three categories where he’s a huge asset. Just don’t let this year’s outburst prevent you from either keeping or drafting a more consistent power threat to pair with him. Let whatever power remains next year be a bonus, not a driving force behind the decision to keep him.