Joe Mantiply
Former All-Star Joe Mantiply's appearance in Game 2 only lasted a third of an inning, but featured two Phillies doubles, which allowed them to extend their lead over the Diamondbacks by three runs. He took over from Merrill Kelly, who already struggled in his 5 2/3 innings pitched against Philly, and did nothing to stop the hemorrhaging. Mantiply's three subsequent appearances in the NLCS showed signs of improvement; he pitched a mostly clean full inning in Game 4 and 2/3 of one in Game 7.
Consistency is going to need to be the key for Mantiply going into the World Series; as an almost everyday bullpen guy who the Rangers haven't seen much of throughout the season, he'll have to stop giving up some scary doubles the next guy has to clean up.