After the German invasion began in June, 1941, Tsyganov served as deputy chief of staff of the Southwestern Main Direction's rear services in August and September, before taking command of 38th Army during its unsuccessful defense of Kharkov in late September and October. However, after his army helped halt the German advance in November, in the following month the "STAVKA" appointed him to command of Southern Front's 56th Army, which participated in that Front's successful winter counteroffensives. After assisting in driving 1st Panzer Army out of Rostov-on-Don in early December and back to the Mius River, 56th Army spent the rest of the winter and spring of 1942 on the southernmost sector of Southern Front, right down to the coast of the Sea of Azov. At the start of the German summer offensive the Army consisted of two rifle brigades and three rifle divisions in the first echelon, backed by two more rifle brigades and a tank brigade with 55 tanks, plus two fortified regions manning fixed defenses in and around Rostov.