Positional scarcity is a huge deal in baseball, and as such, even though fantasy baseball is a game that explicitly ignores defense, it still matters to a certain point. We wouldn't care about Derek Jeter's career if he did it as a first baseman, and we wouldn't draft Jose Reyes in the second round if he were a right fielder.
But, of course, fantasy doesn't always perfectly reflect reality. Sure, you played Edwin Encarnacion at third base in your league for his 150 games and you'll take that all the way to the bank. I've done the same. Still, we all know the only reason they don't call him E5 in Toronto is because he's played all of one game at the position this season.
Encarnacion got 63 games at first base, so at least he won't be a David Ortiz-Billy Butler DH special next season. But throwing him into one of the strongest hitting pools when he was eligible for one of the weakest this season will be a significant ding to his value. He's not the only one. Let's take a look at some hitters who are going to drop a position next year:
Jose Bautista (loses 3B eligibility)
Bautista played just four innings of mop-up work at third base this year. I was one of the Bautista backers this year, personally ranking him third behind Miguel Cabrera and Matt Kemp. Bautista has flaws – he usually doesn't hit for average, doesn't run – but getting such huge power numbers at third base offered something the legion of outfielders and first basemen (i.e. Ryan Braun, Adrian Gonzalez, Joey Votto, etc.) couldn't. Without the ballast of (3B) next to his name (and his injury, of course) Bautista could slip in to the second round next year.
Consider: Bautista's OPS of .886 ranks fourth among third baseman this season. It ranks 16th among outfielders. OPS and fantasy value don't translate perfectly, but the point remains the same.
Michael Cuddyer (loses 2B eligibility)
Cuddyer was one of my favorite value picks this year. A guy with solid power who stole second-base eligibility in 2011 (17 games, somehow) moving to Coors Field? Sign me up. The power was there – he hit 16 home runs in 101 games and his .229 ISO was his second-highest mark ever. But aging is clearly having it's effect – his 19.8% strikeout rate was his worst yet – and without second-base eligibility Cuddyer's value tanks next season. You can abide .260 with 20 home runs, but the Rockies are too bad to elevate his R/RBI totals and he's too old to run. He should fall well below his seventh-ish round draft position next season.
Again: Cuddyer's .806 OPS is 48th among outfielders. It would be fourth among second basemen.
Allen Craig (loses 2B eligibility)
Craig is a better version of Cuddyer, with a 112-point higher OPS. He hits for average, power, and has a great lineup surrounding him, so he still has a very good place in the lineup even after he's limited to the outfield (and first base). Unlike Cuddyer, his value isn't tanked by the limitations of outfield eligibility. Craig is still seventh among outfielders in OPS, so he's one player not to freak out over his lost positional eligibility.
Emilio Bonfifacio (loses SS eligibility)
Bonifacio is a fun player. He stole 30 bases in just 64 games this season, and he's a good bet for 70 or 80 if he comes back healthy next year – the Marlins are going to be bad, and bad teams tend to run more (especially when they're managed by Ozzie Guillen). But it'll be tougher and tougher to absorb his almost non-existent power totals without his eligibility at shortstop, where nobody hits for power anyway. Bonifacio managed just 11 RBI and one homer in 64 games, or about three homers and 28 RBI over a full season.
The average shortstop musters just 12 home runs and 58 RBI per 162 these days. In some leagues he'll still have eligibility at second base (15 games), which was similar this year (but is heavier at the top with players like Robinson Cano and Chase Utley and the like). But if he has to move to the outfield full-time, in leagues with a 20-game cap? He's competing against averages of 18 homers and 71 RBI per 162, which is quite the tradeoff for the steals.
Kyle Seager (loses SS eligibility)
Seager was a very sneaky play at shortstop this season, mustering 16 homers and 78 RBI so far to outpace most shortstops in the power department. He'll run a little bit (12 steals) and his average won't kill a team (.251), making him a well above-average play at shortstop this year. But he'll be forced to move to second base in some leagues (10 games, eight starts) and third base outright in others.
Third base really neutralizes his power. David Wright returned to form and Miguel Cabrera shifted back to third base, and that alone is enough to greatly shift the balance of power at the position. The average third baseman mashed 19 home runs and 80 RBI per 162 so far this season just a year after averages of 14 homers and 71 RBI. Seager will be fine depth this year, but particularly as long as he's constrained by Safeco Field he probably won't be worth starting in 10 or 12-team leagues at third base.
And two final names of note:
Michael Young (loses third-base eligibility in 20-game cap leagues): Young's decline has been apparent all season. If he loses third-base eligibility this year, he's toast – he'll be down to just first base and utility.
Lance Berkman (loses OF eligibility): 2013 will be tough for players to evaluate Berkman if he returns for another season – the injuries almost ended his career, but he's been solid in his 29 games, hitting .263/.385/.461 for the Cardinals. Still, without the outfield eligibility the risk just might be too much – what he's done in his short time this year doesn't play too well at first base.