Diamondbacks GM Dave Stewart joined Mike Ferrin of MLB Network Radio (audio link) to discuss last night’s multi-player deal sending Mark Trumbo to the Mariners. He explained that Welington Castillo (acquired in the deal) was not initially a backstop that had interested him upon taking the helm in Arizona — as he hinted, the club conceivably could have made that move when shipping Miguel Montero to the Cubs — but that the loss of Tuffy Gosewisch forced the team’s hand.