Sergeant Major Carlos A. Ruiz has been selected to serve as the 20th Sergeant Major of the Marine Corps. Sgt. Maj. Ruiz is currently serving as the Command Senior Enlisted Leader for U.S. Marine Corps Forces Reserve and U.S. Marines Corps Forces South. He will replace Sergeant Major of the Marine Corps Troy E. Black during a relief and appointment ceremony slated for Aug. 8, 2023. - Sergeant Major Carlos A. Ruiz has been selected to serve as the 20th Sergeant Major of the Marine Corps. Sgt. Maj. Ruiz is currently serving as the Command Senior Enlisted Leader for U.S. Marine Corps Forces Reserve and U.S. Marines Corps Forces South. He will replace Sergeant Major of the Marine Corps Troy E. Black during a relief and appointment ceremony slated for Aug. 8, 2023.