In a sudden slew of roster moves, the Red Sox added depth behind the plate in Erik Kratz, activated Justin Masterson, and sent down Rusney Castillo and Steven Wright to make room.
Let's go down the line, shall we?
The addition of Erik Kratz, claimed off waivers from the Royals this past week, was necessitated by the foot sprain suffered by Blake Swihart against the same team. The Sox briefly had to rely on Mike Napoli as their depth behind the plate, but will certainly feel more comfortable with an actual second healthy backstop ready to go.
Swihart, for his part, is still day-to-day. With Kratz on the active roster now and Brock Holt effectively backing up every other position on the field, the Sox can afford to wait a little longer to see if he heals up without a disabled list trip.
Justin Masterson makes his return to the team after better than a month's absence. The Red Sox were likely just trying to get him out of the rotation when they put him on the disabled list, and they've succeeded in that, with Masterson set to come out of the bullpen. Unfortunately, as a ROOGY he generally lacks the ability to throw strikes, and there's no guarantee the change in role will help his velocity any, but it was either that or a trip to the waiver wire.
Rusney Castillo being optioned back to Pawtucket probably comes too late, if anything. He's been out of the starting lineup for a week now in favor of either Alejandro De Aza or, when he's not playing the infield, Brock Holt. Frankly there's no small chance that Castillo's struggles this year are already due to inconsistent playing time caused by the injuries he suffered in March and April, making his presence on the bench ill-advised at best.
Finally, Steven Wright will find himself back in Pawtucket after a successful stint in the rotation and a less successful stint in the pen. It wouldn't be surprising if the Red Sox get him back in the rotation down there, with an eye towards having him join Brian Johnson as Boston's immediate rotation depth.