Bringing UJ in at all in that situation was stupid, but the most unforgivable sin from last night is not bringing Britton in after UJ put runners on. For God's sake, you have the best closer in baseball who also happens to be a K and/or groundball specialist sitting on the bench, NOT EVEN WARMING UP!
When you are on the road, extra innings become sudden death, this happened to also be an elimination game, which added to the importance of not giving up anything in this situation. The O's mindset should've been to extend the game for as long as possible and hope that you can get a run somehow - in a situation in which the heart of the Jay's lineup is coming up, you're best option to simply extend the game is to put your best pitcher out there. Hopefully you get through the meat of the order and you buy 1 or 2 more innings to try to score.
Bottom line, use your best relievers first... extend the game as long as you can... then, if you still haven't scored after Britton, Hunter, and Bundy have pitched, UJ is your only option and he can take you the rest of the way. In this case you can at least say you used your best players to give your offense the best chance of stealing a win in extras.
BTW, I am not saying that the offense gets a pass here either. I hear "the offense needs to contribute too, so this isn't on Buck" argument, but this is irrational. They are both causes of the loss - but Buck's decision was completely in his control, whereas our shit hitters don't consciously decide to strike out.
I think it's time to have an honest conversation in the FO. Let's be honest, the O's are not going to be able to afford Manny so we need to trade him this offseason to get the best possible value back. Britton had a career year and will likely not see the same kind of success next year given the stikezone changes, if the O's are smart, they'll trade him for some prospects as well.
I want a rebuild around the BP (except Britton) and SP. Keep guys like Kim and maybe Schoop, but surround them with a good balance of OBP and power. Let's get serious about building a real contender and not a one-dimensional gimmic.