Born in Baltimore, MD and the son of a soldier, MajGen Rock was commissioned in 1988 upon graduation from the US Naval Academy. Designated a Naval Aviator in 1990, he flew the CH-46E Sea Knight while serving in HMM-263 (1991-95). Following duty as the Air Officer for 3rd Bn, 8th Mar (1995-96), he returned to the cockpit as a flight instructor at HMT-204 (1997).

Selected to conduct MV-22 Osprey operational testing at HMX-1 (1997-2000), he was then an instructor at VMMT-204 (2000-03) and a “plankowner” for the Corps' first operational test squadron, VMX-22 (2003-05). Upon his return from 2d MAW (Forward) staff in G-3 (Plans) in Iraq (2005), he took command of VMM-263, the Marine Corps' first operational MV-22B squadron, and again deployed to Iraq in support of OIF (2006-08).

After squadron command, MajGen Rock attended the National War College (2008-09) and commanded VMMT-204, the Joint USMC/USAF MV-22B training squadron (2009-11). Subsequent O-6 duties included the Joint Staff J-5 Strategic Plans and Policy Directorate (Deputy Directorate-Asia) (2011-13) and the Aviation Expeditionary Enabler Branch Chief and V-22 Cell Lead at Headquarters Marine Corps (2013-14).

General Officer assignments began with Assistant Wing Commander and interim Commanding General of 2d Marine Aircraft Wing (2014-15). He then served in Joint duty as the J5 - Director of Strategy, Policy, & Plans for US Southern Command (2015-17). Shifting to Okinawa, Japan, General Rock served as the 27th Commanding General of Marine Corps Installations Pacific - Marine Corps Base Camp Smedley D. Butler (2017-19).

Prior to his current assignment, Major General Rock was the Commanding General, 3d Marine Expeditionary Brigade and Deputy Commanding General, III Marine Expeditionary Force (2019-20).