The playoffs are kind of a crap-shoot. there. While you will often see one of the top teams in the league win the Fall Classic (the 103 win Cubs in 2017, 97 win Red Sox in 2013, or 103 win Yankees in 2009 are the first to come to mind), a team that barely squeaks in always has a chance (*cough* 2006 Cardinals *cough).
As loathe as I am to talk about the San Francisco Giants, their win in 2014 is the best story we can tell to explain why the Sox have a chance in October.