Army Group Don
In January 1943, von Mackensen's First Panzer Army became attached to Army Group Don under Field Marshal Erich von Manstein. The month after that, von Manstein redeployed the First Panzer Army together with the Fourth Panzer Army to counter-attack the Soviet breakthrough from the Battle of Stalingrad. The First Panzer Army contributed to the success of the Third Battle of Kharkov in March 1943. In July 1943, the Army, with the help of the XXIV Panzer Corps, repelled the Soviet Izyum-Barvenkovo Offensive. In October 1943 Soviet forces crossed the Dnieper River between Dnipropetrovsk and Kremenchug. The First Panzer Army counter-attacked along with the 8th Army, but failed to dislodge the Soviet forces. At the end of that month, as the Red Army closed in on Kiev, von Mackensen was replaced by Colonel-General Hans-Valentin Hube.