I won't pretend to know the meaning of JJ's "unavailability". Here's my guess: Woodruff warming in the 9th signaled to me that it was Hader's inning. They were either going to lose the game with Hader on the mound in the 9th, or Woodruff was coming in to pitch the 10th in a tie game. This is pretty obviously what was going on. JJ was being saved for today. Woodruff could have gone multiple innings and extras, saving the rest of the pen. So then why the "undisclosed reasons" line? Just say he was being saved for today. and I'm not suggesting we have a right to know what's going on but I don't think it was a simple roster management thing. Seems JJ is doing OK and that's the important thing.