The Kharkov and Donbas operations were started on 25 February by the new Central Front led by Rokossovsky, with the forces freed after the surrender of the Germans in Stalingrad on 2 February. The operations were aimed at Army Group Centre in the north and timed to coincide with the expected successes of the Soviet operations in the south. Army Group South escaped encirclement and prepared a counter-offensive, which led to the Third Battle of Kharkov and the stabilisation of the front. The disaster at Stalingrad was the end of Case Blue and the territorial gains had been reversed by the end of 1943, except for the Kuban bridgehead on the Taman peninsula, retained for a possible second offensive to the Caucasus, which was held until 19 October 1943.