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Video by Maj. Jacqwayne Griffin

SFC Jake R. Mrzena - 2025 Drill Sergeant Hall of Fame Inductee

108th Training Command- Initial Entry Training

Sept. 18, 2025 | 1:03

SFC Mrzena was assigned as a Drill Sergeant on December 10, 2019, and served for five and a half years in this role. During his tenure as a Drill Sergeant, he successfully completed two 22-week One Station Unit Training (OSUT) cycles, training over 500 soldiers.

On January 10, 2021, SFC Mrzena was selected to be a Drill Sergeant Leader (DSL) at the United States Army Drill Sergeant Academy, where he served for three and a half years. In this capacity, he had a significant impact on the Drill Sergeant program, training 15 classes of Drill Sergeants and producing 1,800 Drill Sergeants for the Army. He also played a crucial role in designing the Defender Field Training Exercise (FTX), which enhanced the tactical competency of new Drill Sergeants and their ability to train basic trainees in lethality. Additionally, he was instrumental in developing and implementing the Defender Pickup, which incorporated the "First 100 Yards" pickup into the Drill Sergeant Academy curriculum.

On the 60th anniversary of the Drill Sergeant Program, SFC Mrzena was named the 2025 U.S. Army Reserve Component Drill Sergeant of the Year and was assigned to Fort Eustis, VA. In this role, he played a vital part within the Center for Initial Military Training (CIMT), advising the Commanding Generals and Command Sergeants Major of both the Training and Doctrine Command (TRADOC) and CIMT on the current status of Drill Sergeants, the Drill Sergeant program, and training in Basic Combat Training, Advanced Individual Training, and One Station Unit Training.

SFC Mrzena also completely rewrote the Soldiers Handbook, known as the Soldier’s Blue Book, later updating it to the Soldier’s Green Book. He was responsible for updating TRADOC Regulations 350-6 and 350-16. Furthermore, he designed the Holistic Drill Sergeant Welfare Program and was a key contributor to the complete redesign of Basic Combat Training as part of the Basic Combat Training Transformation Project.