Understanding kinematics and movement variability (MV) of the axial skeleton (head, thorax, spine, and pelvis) during scrums in Rugby Union is important from a performance and injury prevention perspective. The aim of this study was to investigate repeatability (or MV) of axial skeleton kinematics during one-man simulated scrums. Nine front row players performed scrums against a scrum machine. Results showed high levels of repeatability. The outcomes of this study suggest that the difficulty in performing scrums well might not reside in the basic technique, but be more associated with external factors, such as the interaction between players in a full scrum. Therefore, the results suggest that expert movement may better be achieved by practicing scrums under more realistic conditions than against a scrum machine.