Career
He was signed by the New York Jets as an undrafted free agent in 2006. He played college football at Lafayette. Costanzo has also played for the Buffalo Bills, Cleveland Browns, and Chicago Bears.
He is currently the head coach at Paramus Catholic High School (New Jersey).
He played high school football at Ramapo High School in his New Jersey hometown as a linebacker and a tight education He helped lead his team to two state championships.
He played linebacker and tight end, and was awarded the Award. In his high school career, he recorded 210 tackles, 24 sacks, and 11 blocked punts.
He was named three times to the All-League first team, as well as the All-Bergen County first team
2002 In 2002, Costanzo recorded 34 tackles and finish fourth among the Leopard freshmen in tackles. He also made two sacks, while leading the team in forced fumbles with two. 2003 In 2003, he ranked third among the Leopards and seventh in the Patriot League with 94 total tackles.
He also blocked a three kicks, and recorded 13 stops and blocked a PAT against the Colgate Raiders.
He also recorded 12 tackles and blocked two punts against Towson. He also recorded 12 tackles against Georgetown and Columbia, as well as recording his first career interception against Holy Cross.
2004 In 2004, he was the team"s Most Outstanding Linebacker, as he ranked second on the team and seventh in the Patriot League with 93 tackles. He had 5.5 sacks, and recorded 1.5 sacks against Bucknell.
Against the Holy Cross Crusaders, he made 12 tackles, forced a fumble, and blocked an extra point.
Against the Columbia Lions, he made 11 tackles, a sack and a fumble recovery. Against the Fordham Rams, he recorded a sack versus Fordham, as well as blocking a fourth-quarter field goal against Colgate, along with recording a sack against Delaware.
College stats New York Jets Costanzo was signed as an undrafted free agent by the New York Jets in 2006, and was on the practice squad until 2007.
Buffalo Bills Costanzo played for the Buffalo Bills in 2007 and 2009 seasons. Cleveland Browns In the 2010 season, Costanzo played in ten games before injuring his groin and being placed on injured reserve.
San Francisco 49ers On June 3, 2014, Costanzo signed a one-year deal to return to the 49ers. He was released later into the year.
Chicago Bears Costanzo was signed by the Chicago Bears in 2012 on a two-year deal.
General manager Philosophy Emery commented, "Blake has done some dynamic things as a special teams player, as is evident from his four forced fumbles with one of them in a playoff game against New Orleans this past year." Costanzo ended the 2013 season leading the Bears with 17 special teams tackles.