Castillo has spent most of his career coaching offense. Here is a snippet from his wikipedia page and link: http://en.wikipedia.org/wiki/Juan_Ca...rican_football)

"Castillo became the defensive coordinator on February 2, 2011.[5] The hiring was met with surprise by players, fans, and members of the media primarily because Castillo had not coached the defensive side of the ball since he was at Kingsville in 1989.[6][7]"