He joined the Baltimore Ravens as a coaching assistant from 2002 to 2003. He stayed with the Ravens as assistant defensive line coach in 2004 and as outside linebackers coach from 2005 to 2008. Pettine became defensive coordinator for the New York Jets from 2009 to 2012 and then for the Buffalo Bills in 2013. He got his first NFL head coaching job in 2014 with the Cleveland Browns.