Eric Mangini

Eric Anthony Mangini (born January 19, 1971) is an American football coach who last served as the defensive coordinator for the San Francisco 49ers of the National Football League (NFL). Mangini had been with the 49ers since 2013 and served as the team's tight ends coach for two seasons before being promoted to defensive coordinator in 2015, only to be fired in 2016 by new head coach Chip Kelly.Mangini, facetiously known as "the Mangenius," is a former head coach, having served as the coach of the New York Jets from 2006 until 2008 and the Cleveland Browns in 2009 and 2010. Prior to taking his position with the 49ers, Mangini was an NFL analyst for ESPN. Since being fired by the 49ers, Mangini has become an analyst for Fox Sports 1.Mangini is known for being a former assistant under Bill Belichick, serving under him as a defensive assistant while Belichick was the defensive coordinator with the Jets and later following him to the New England Patriots, where he succeeded Romeo Crennel as defensive coordinator in 2005 after Crennel took the head coaching position with the Browns (a position he would also be succeeded in by Mangini).