The Russians smartened up in 42 & learned how to fight a withdrawal.

As planned, the offensive began with rapid advances reminiscent of the campaigns of the previous year; within a month, on 27 July, the Russians evacuated Rostov without a fight. Meanwhile the Panzer Armies smashed through and began encircling the thinly spread Soviet Sixty-Second Army defending the Don River basin. As a counter measure the Soviets sent the First Tank Army striking out from the left bank of the Don towards Kalach, threatening the flank of the Fourth Panzer Army. "The . . . counter-stroke did not lead to the routing of the German forces which had broken through the Don but, as later events demonstrated, it frustrated the enemy's plan of encircling and annihilating the Soviet Sixty-Second Army."[4] The Russians had learned to fight a withdrawal. This campaign would not be a repeat performance of the blitzkriegs of 1941; the Germans would seize territory, but few prisoners