At the start of the year it was pretty easy to view Kyle Seager as a future utility infielder with some potential to be more than that. A third of the way through the season, it's pretty easy to view Kyle Seager as an everyday player, perhaps even one who is a bit above average. It's also pretty easy to view Kyle Seager as a better fielder than Ackley. The fact that the Mariners occasionally move Ackley to DH or 1B to get Seager some time at 2B suggests they think the same thing. And the limited UZR data also supports it.
The other day at USS Mariner, Dave wrote a post about lots of potential moves. And then in the comments lots of people talked about moving Ackley to the outfield. And then Dave told them to shut up. But they wouldn't shut up. And I think they wouldn't shut up because maybe they were onto something. But moving Ackley to the outfield is a pretty bad way of dealing with what they were onto. Maybe there's a better way of doing it.
In about 7% of a season at 2B, Seager is about 3.5 wins above average. Certainly we should regress those numbers somewhat, but it's easy to imagine him being at least half a win better than the league average Ackley.
But in about half a season at 3B, Seager is essentially league average. Those defensive skills he has at 2B don't completely translate to 3B. Sure he might be a bit better this year than he was last year, and perhaps that is because he's getting more familiar with it. But I just don't see him becoming Adrian Beltre over there, though there is the possibility of him having that level of defensive value at 2B.
So we have two everyday secondbasemen on the team, and the one playing third is the better defender, though when moved to third he isn't actually better. You can see why people would want to move the other secondbaseman elsewhere. And maybe I agree, I just don't think it should be to the outfield.
The Mariners going forward are probably losing at least half a run a year, maybe more, by playing Seager at third and Ackley at second. And they are both under team control for another five or six years, so they aren't getting that half a run back when (hopefully) it starts to matter. I think the best way to extract value from this is to trade one of them. They both look to be above average, although Ackley is still probably projected to do better than Seager going forward. But the point is either one of them could be a legitimate piece on a contending team. I say trade Ackley along with some pitching prospects for a young, cost-controlled, proven outfielder or thirdbaseman. We shouldn't trade for a prospect at this point, even someone as ready as Montero was, but someone who is already there. We now have the minor league depth to be able to do that. Get someone like Alex Gordon, Mike Stanton, Andrew McClutchen, or Justin Upton. Of the teams employing these players, the Royals seem most in need of someone at 2B. I don't know which of our prospects to package with Ackley to get it done, and I don't know which teams would be most willing to turn loose of their top players. But I think this is the direction the team should consider long term, rather than playing either one of them out of position.