As mentioned earlier, Hitler had been worried for months about the prospect of crisis in the middle reaches of the Don. This front was mainly defended by the Italian 8th Army and remained part of Weix's Army B. Zone. Before and after Manstein launched the "Winter Storm", Hitler wanted to strengthen the Italian defenses somewhat, and took some emergency measures. Knowing that the Italians lacked anti-tank weapons, he immediately ordered the delivery of a batch of captured French anti-tank guns.
It also set up the German 27th Panzer Division as a reserve in the rear of the Italian army, and also used 3 German infantry divisions to consolidate the positions of 9 Italian divisions. Additional were the SS "Shudt" brigade (2 motorized battalions as the backbone), several German guards and police regiments, and even Hitler's own guard battalion (with a company of about 21 tanks).
The Nazi Fuehrer knew very well that once the Italian army was defeated, the Red Army would rush through manstein's empty rear and plunge straight into Rostov. This means that all 700,000 troops on the southern front will be cut off from retreat.
In fact, this was exactly what the Soviet Army's "Saturn" campaign plan was. Vatutin's Southwestern Front divided its troops into two routes. The northern road was the 1st Guards Army (and flank of the 6th Army of the Voronezh Front), from Shangmamun to the south; the eastern road was the 3rd Guards Army, from Bokovskaya to the west. The two Soviets first encircled and destroyed the Italian 8th Army, and then rushed to Rostov via Mile rovo.