He was waived on September 4, 2010, and re-signed to the practice squad the next day. On December 8, 2010, Rey was promoted to the Bengals active roster and played in his first two career games in Weeks 15 and 16.[3]
His first career start came on October 31, 2013 against the Miami Dolphins on Thursday Night Football. Due to an injury to starter Rey Maualuga, Rey was called upon to start in multiple games in 2013, and then again in 2014 with injuries to starter Vontaze Burfict. He showed an ability to line up at any linebacker position and had a strong command of the defense, often calling plays and setting formations when in the game.
Rey signed a new two-year deal with the Bengals on March 14, 2014.[4] On March 9, 2016, Rey signed a three-year, $11.5 million extension with the Bengals.[5]