Manstein's Counterattack
What was known to the Germans as the Donets Campaign took place between 19 February and 15 March 1943. Originally, Manstein foresaw a three-stage offensive. The first stage encompassed the destruction of the Soviet spearheads, which had over-extended themselves through their offensive. The second stage included the recapture of Kharkov, while the third stage was designed to attack the Soviets at Kursk, in conjunction with Army Group Center—this final stage was ultimately called off due to the advent of the Russian spring thaw (Rasputitsa) and Army Group Center's reluctance to participate.
Read more about this topic: Third Battle Of Kharkov