However, his brilliance and accomplishments so soon in his career made his superiors jealous, and they falsely accused him of desertion during battle. The conspiracy was led by General Yi Il (이일; 李鎰; 1538–1601), who would later fail to repel the Japanese invasion at the Battle of Sangju. This tendency to sabotage and frame professional adversaries was very common in the later years of the Joseon military and government. Yi was stripped of his rank, imprisoned, and tortured. After his release, Yi was allowed to fight as an enlisted soldier. After a short period of time, however, he was appointed as the commander of the Seoul "Hunryeonwon" (a military training center) and was later transferred to a small county, to be its military magistrate.