In 1918 as an officer of the General Staff he was the commander of the 1st Unit of the Army of UNR. In 1919 he became the chief of staff of the "Independent Corps of Sich Riflemen". In 1920, after UNR leader Symon Petliura's alliance with Poland, he became the commanding officer of a regiment-sized "6th Ukrainian Infantry Division" of the 2nd Polish Army under General Antoni Listowski. He commanded the unit in the April-June 1920 Kiev Offensive of the Polish Army. Bezruchko led the defense during a Bolshevik offensive against Zamość in August-September 1920.