The struggles of the Royals bullpen have been the biggest weakness of this team, either that or the outfield production. Still, heading into the playoffs I am somewhat optimistic that the bullpen will be a lot more solid in October.
The main reason for optimism is based around Chris Stratton, Will Smith, and Angel Zerpa not being in the pen. To be fair to Zerpa, he was pretty good through much of the first four months of the season. He just has not looked good at all recently. The other two have struggled a lot, though Smith had a period where he was getting it done in low leverage.