This is a pretty unexpected development. As blank_38 pointed out, at the time of the deal, Kevin Towers made fairly definitive proclamation that the PTBNL was the most important part from the Arizona perspective.
"I would say the player to be named later is someone we value as a prospect. Of course, we can't announce who that is yet. That's not taking anything away from Choate. But I'd say probably the key player in the deal, with the players from Tampa Bay, will be the player to be named later."
I'm sure there are good reasons for Glaesmann's decision - though his Twitter account contains absolutely nothing at this point that would even hint at the move, and it seems to have come as a major surprise to just about everyone. Jack Magruder just Tweeted
Dbacks Glaesmann on retiring: "Although the decision was not easy it was best move for me. The passion for the game was not there anymore."
— Jack Magruder (@JackMagruder) February 28, 2014
Welp. Sounds like Glaesmann is simply burned out on the game at the grand old age of 23. Is it too late to "unname" him? Can we get a different player to be named later from Tampa? As is, getting rid of Heath Bell still cost us David Holmberg + a suitcase of cash, and now all our hopes for anything positive are pinned on Justin Choate, an undrafted free agent who hasn't yet pitched above Low-A ball and has 40.2 pro innings under his belt, not counting his time with the indie Roswell Invaders. No pressure, Justin. :)