The success of Leyser’s attack suggests that if Paulus had established a strong mobile reserve before the offensive, he could have struck south with it, a distance of little more than fifteen miles, and quite easily smashed the lower arm of the encirclement. On the following day, he could then have sent it north-westwards in the direction of Kalach to meet the main threat from the northern offensive. But this presupposed a clear appreciation of the true danger, which both Paulus and Schmidt lacked.
On that morning of Friday, 20 November, at about the time the bombardments commenced south of Stalingrad, Kravchenko’s 4th Tank Corps, nearly twenty-five miles deep into the rear beyond Strecker’s XI Corps, switched its advance south-eastwards. The 3rd Guards Cavalry Corps was meanwhile turning in to attack XI Corps from behind. Strecker was trying to establish a defence line south from the greater Don bend to protect this open gap behind the whole army. The bulk of his corps meanwhile faced the Soviet 65th Army to the north which kept up the pressure, with constant attacks, to hinder any redeployment.
With the Romanians ‘fleeing wildly, most of them leaving behind their weapons’, the 376th Infantry Division had to pull round to face westwards, while trying to make contact with part of 14th Panzer Division to its south. The Austrian 44th Infantry Division also had to redeploy, but ‘much material was lost because it could not be moved owing to the shortage of fuel’.
To their south, the panzer regiment of 14th Panzer Division still had no clear idea of the enemy’s direction of approach. Having advanced westwards for a dozen miles, it then withdrew in the afternoon back to Verkhne-Buzinovka. On the way, it ran into a flanking regiment of the 3rd Guards Cavalry Corps which it virtually annihilated. Over the first two days, the panzer regiment destroyed thirty-five Soviet tanks. On the other hand, an unprotected flak detachment, using its ‘eighty-eights’ as anti-tank guns, was overrun by a Russian attack.
‘The catastrophic fuel situation’ continued to hamper the other panzer and motorized divisions, starting to move westwards from Stalingrad to reinforce this new front. They were also suffering from a shortage of tank crewmen after Hitler’s order to send every available man into Stalingrad as infantry. The other decision bitterly regretted was the withdrawal of Sixth Army’s horses to the west. The new war of movement suddenly imposed by the Russians forced German infantry divisions to abandon their artillery.
The Romanian collapse accelerated as the Soviet spearheads went deeper. Few of their rear support troops had been trained to fight and staff officers fled their headquarters. In the wake of the advancing tanks, wrote one Soviet journalist, ‘the road is strewn with enemy corpses; abandoned guns face the wrong way. Horses roam the balkas in search of food, the broken traces dragging on the ground after them; grey wisps of smoke curl up from the trucks destroyed by shellfire; steel helmets, hand grenades and rifle cartridges litter the road.’ Isolated groups of Romanians had continued to resist on sectors of the former front line, but the Soviet rifle divisions from the 5th Tank Army and 21st Army soon crushed them. Perelazovsky had contained a Romanian corps headquarters which, according to General Rodin, was so hurriedly abandoned that his 26th Tank Corps found ‘staff papers scattered on the floor and officers’ fur-lined greatcoats hanging on racks’—their owners having fled into the freezing night. More important for the Soviet mechanized column, they captured the fuel dump intact.
Meanwhile, the 22nd Panzer Division, unable to resist the T-34s of 1st Tank Corps, had retreated. It made an attempt to attack north-eastwards the following day, but was soon surrounded. Reduced to little more than the equivalent of a company of tanks, it later fought its way out and retreated south-westwards, harried by the Soviet 8th Cavalry Corps.
In the meantime, Rodin’s 26th Tank Corps, having smashed part of the 1st Romanian Panzer Division which got in its way, also started its advance across the open steppe to the south-east. The Soviet columns had been told to forget the enemy left behind and concentrate on the objective. If Luftwaffe air reconnaissance had been able to identify the roughly parallel courses of the three tank corps during the afternoon of 20 November, then alarm bells at Sixth Army headquarters might have rung earlier.
The main Romanian formation still fighting effectively at this time was the ‘Lascar Group’. This consisted of remnants from the V Army Corps, gathered together by the intrepid Lieutenant-General Mihail Lascar, when cut off between the two great Soviet armoured thrusts. Lascar, who had been awarded the Knight’s Cross at Sevastopol, was one of the few senior Romanian officers the Germans really respected. He held out on the assumption that XXXXVIII Panzer Corps was coming to his relief.
Sixth Army headquarters, twelve miles north of Kalach at Golubinsky, seems to have started the morning of Saturday, 21 November, in a relatively optimistic mood. At 7.40 a.m., ‘a not unfavourable description of the situation’ was dispatched to Army Group B. Paulus and Schmidt, who still perceived the attacks on Strecker’s left flank by the 3rd Guards Cavalry Corps as the main threat, clearly thought that their forces brought westwards from Stalingrad would transform the situation.
During the course of that morning, however, Paulus and Schmidt received a series of nasty shocks. Different signals all pointed to the same conclusion. Army Group B warned them that Sixth Army’s southern flank was now threatened from both sides. A report came in that a large armoured column (in fact part of Kravchenko’s 4th Tanks Corps) was less than twenty miles to their west. It was heading for the Don High Road, the showpiece of German military engineering on the west bank which linked most of the bridges on that vital stretch of the river. Sixth Army had no troops in the area capable of meeting the threat. To make matters worse, many of Sixth Army’s repair bases and supply depots lay exposed. Paulus and Schmidt at last recognized that the enemy was aiming for a full encirclement. The diagonal Soviet thrusts, from both the north-west and south-east, were almost certainly aiming for Kalach and its bridge.
The disastrous German reactions to Operation Uranus had lain not just in Hitler’s belief that the Russians had no reserves, but in the arrogant assumptions of most generals as well. ‘Paulus and Schmidt had expected an attack,’ explained an officer with Sixth Army head-quarters, ‘but not such an attack. It was the first time that the Russians used tanks as we did.’ Even Richthofen implicitly admitted this when he wrote of the enemy offensive as ‘for him an astonishingly successful breakthrough’. Field Marshal von Manstein, on the other hand, felt (perhaps with the benefit of hindsight) that Sixth Army headquarters had been far too slow to react and extremely negligent in its failure to foresee the threat to Kalach—the obvious Don crossing between the two breakthroughs.
Soon after midday, most of Paulus’s headquarters staff were sent eastwards to the railway junction of Gumrak, some eight miles from Stalingrad, so as to be close to the bulk of the Sixth Army. Meanwhile, Paulus and Schmidt flew in two Fieseler Storch light aeroplanes to Nizhne-Chirskaya, where they were joined by General Hoth on the following day for a conference. At Golubinsky, they left behind columns of smoke rising into the freezing air from burning files and stores, as well as several unserviceable reconnaissance aircraft on the adjacent airstrip which had been set on fire. In their hurried departure, they also missed a ‘Führer decision’ relayed on by Army Group B at 3.25 p.m. It began: ‘Sixth Army stand firm in spite of danger of temporary encirclement.’
There was little hope of holding positions on that afternoon of 21 November. The accumulation of delays to the panzer regiment of 16th Panzer Division had left a hole below Strecker’s XI Army Corps and the other assorted groups attempting to form a new defence line. This was rapidly exploited by the Soviet 3rd Guards Cavalry Corps and 4th Mechanized Corps. Strecker’s divisions, increasingly threatened from the north and north-east as well, had no option but to start withdrawing towards the Don. The ill-considered plan of sending the Sixth Army’s panzer regiments westwards was now revealed to have been a dangerous diversion of effort.