Well, de Aza is the lefty back up outfielder if they decide they want to send Goodwin down so he can play every day. I sense that this is a move to create that sort of option, which they'd do if Goodwin shows he's not ready to take the bulk of the playing time (either through undeperformance or a continuing commitment to Taylor). You'd be looking at a LF
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of de Aza and Heisey while Werth is out, Taylor full time in CF, and Future Yankee in right.
I have not broken out the arrow pointing to the avatar in a while. I am a big believer in platoons, and I was especially pushing for this in the pre-2012 era when we had few players worthy of full-time roles. I pushed for this so much I adopted the Platoon poster as my avatar