Will Welington Castillo up his defensive game, or become a liability?
A top-flight MLB catcher will log 1000 or so innings behind the plate in a season. None of the Diamondbacks catchers even really came close to that in 2015. Welington Castillo had 626, with Jarrod Saltalamacchia and Tuffy Gosewisch logging over 300 apiece. Defensively, none of them are anything to write home about, and this is one position where someone either needs to step up, or the team needs to make a change. Castillo gives up a lot of extra strikes, and his pitch framing is well below average. In fact, the only catcher on the team in 2015 NOT below average was Oscar Hernandez, who barely played. All of them were also below or well below average on stolen bases allowed.
With the question marks in the bottom of the starting rotation, support behind the plate becomes more crucial. Castillo has a solid bat and puts up good offensive numbers, but may well give away more than he earns. Gosewisch is a slight upgrade defensively, but keep in mind: that makes him closer to average, but still below.
If a serious run on the division and post-season should occur, one either one of these guys is going to have to step up his defense, or a possible upgrade at this position could be necessary down the stretch. Do the Diamondbacks have a plan for this, and can one of their current players rise to the challenge? Okay, that’s two questions. This team is projected to win 84 to 88 games by most systems. Fixing the defense behind the plate could be a way to bump that up a few.