I pulled this out separately so it wouldn't get lost in the previous post, but again, there are several scenarios in which Moncada could end up in the outfield for Boston and they aren't difficult to imagine. If the Red Sox can build a package for, say, Quintana around JBJ in January, Moncada would probably start getting work in as an outfielder immediately, assuming the club thinks Shaw can continue being a passable starter at third for a few years, or that Panda has a chance to give them another season or two there. Or they could decide to go after Justin Turner. Or they might see a trade opportunity for a third baseman.
I think it's probably more likely (and is preferable by a long shot) to retain JBJ, Mookie and Benintendi as the starting outfield, keep Moncada exclusively at third, and roll the dice with Price, Porcello, Pomeranz, Rodriguez, Wright, Buchholz and the AAA fodder for the rotation next year, but it's really not hard to see them going in another direction.