Appointed commander of the 172nd Rifle Division on 9 September, Kostitsyn led the division while it began forming in the Moscow Defense Zone. He was transferred back to command the 183rd Rifle Division, now in the Reserve of the Supreme High Command, on 30 September. Between 7 and 20 January 1943 the 183rd was relocated to the Voronezh Front, joining the 40th Army. Kostitsyn led the division in the Ostrogozhsk–Rossosh Offensive, the Voronezh–Kastornoye operation, and the Third Battle of Kharkov. For his leadership of the division in the Kharkov Offensive Kostitsyn was awarded the Order of the Red Banner on 25 March. In March the division fought in the defense of Kharkov during the latter, and was forced by the German advance to retreat to the Seversky Donets, after which it defended positions in the area of Krutoy Log and Nizhny Olshanets. At the beginning of April it was assigned to the army rear defensive line near Prokhorovka. The division defended its positions at the beginning of the Battle of Kursk on 6 July, repulsing German attacks. As part of the 69th Army's 35th Guards Rifle Corps, Kostitsyn led the 183rd during the subsequent Soviet offensive. The attack began on 21 July, attacking German lines between Novy Oskol and Verkhnye Olshanets, which were captured before the division advanced to the defensive line between Height 217.4 and Dalnyaya Igumenka. On 24 July Kostitsyn and several staff officers were killed by a direct shell hit to the division command bunker. Buried in Novy Oskol, he was posthumously awarded the Order of the Patriotic War, 1st class on 24 August for his leadership of the division at Prokhorovka.