Jeffrey Cobb is an American professional wrestler and former amateur wrestler. As of May 2025, he is signed to WWE, where he performs on the SmackDown brand under the ring name JC Mateo. He is best known for his tenure in New Japan Pro-Wrestling (NJPW), where he was a member of United Empire.
In NJPW, he is a former one-time NEVER Openweight Champion and a three-time IWGP Tag Team Champion. He also wrestled for various promotions, such as Lucha Underground (as the masked wrestler Matanza Cueto) where he is a former one-time Lucha Underground Champion, Ring of Honor (ROH), where he is a former one-time ROH Television Champion, as well as Pro Wrestling Guerrilla (PWG) where he is a former one-time PWG World Champion, one-time World Tag Team Champion, and is also the winner of the 2018 Battle of Los Angeles.
As an amateur wrestler, Cobb represented Guam at the 2004 Summer Olympics, where he became the nation's flag bearer in the opening ceremony and competed in the men's light heavyweight freestyle category. He transitioned to professional wrestling in 2009.