What Red Sox’ Craig Breslow said about trading Marcelo Mayer, once viewed as ‘part of a core’

The Red Sox traded 23-year-old shortstop Marcelo Mayer to the Giants on Monday. Boston got reliever Erik Miller and prospect Carlos Gutierrez in return. Chief baseball officer Craig Breslow said, “He was a really big part of this organization and someone that was looked upon to be part of a core.”