Fun fact: Koji Uehara just completed a Perfect Game for the Red Sox. Yeah, aware that's not really a 'thing' for relievers, but after mowing down the Yankees in order last night, he's now retired his last 27 batters in a row without a baserunner.
So sure, not really a thing, but neat accomplishment nonetheless. Hasn't had a baserunner since early/mid August, and has been getting plenty of work.
Guy is fun to watch, and definitely came out of nowhere to latch onto the Closer role. Then again, if you compare his stats over the past couple years, he's statistically the best in the game. 1.12 ERA on the season, 64 IP. And since taking over as Closer, his ERA is actually 0.27. (that was before last night, so is probably slightly LOWER than that!)