Bobby Parnell threw roughly 700 curveballs in the ninth inning last night. (And gave up two hits on fastballs. Go figure.) Rob Castellano over on Amazin’ Avenue has a breakdown of Parnell’s pitch selection, so go check out there for more on that.
For my brief take: Parnell’s curveball was his best pitch last night. He got into good counts with it, but he couldn’t command his fastball and put hitters away when he went back to the heat. Thole would set up on the outside corner, but Parnell put his fastball right in the middle of the plate.
Parnell is really, really close to being a dominant reliever, but only if he can use his curveball and fastball interchangeably. His curveball’s developed enough where he can use it effectively and almost-exclusively, as he did last night. But he needs to be able to put his fastball in the right spots after setting it up with curveballs.
Patrick John Flood (blog) 
If the fastball wasn’t being commanded, and he was getting swing and misses on the curveball, I’m not sure why he ever went back to the fastball. Also, I was losing my mind screaming “…they’re sitting on the fastball!!” But Bobby P. never got the memo. Go figure.