Kursk. Overall German casualties are more difficult to come by but clues are provided by examining the casualties of the SS Panzer Corps, taking into consideration that the Waffen-SS divisions were frequently deployed where the fighting was expected to be the harshest. By 17 March, it is estimated that the SS Panzer Corps had lost around 44% of its fighting strength, including around 160 officers and about 4,300 enlisted personnel. As the SS Panzer Corps began to emerge from the city, they engaged Soviet units positioned directly southwest of the city, including the 17th NKVD Brigade, 19th Rifle Division and 25th Guards Rifle Division. Attempts by the Red Army to re-establish communication with the remnants of the 3rd Tank Army continued, although in vain. On 14–15 March, these forces were given permission to withdraw to the northern Donets River. The Soviet 40th and 69th armies had been engaged since 13 March with the Großdeutschland Panzergrenadier Division, and had been split by the German drive. After the fall of Kharkov, the Soviet defense of the Donets had collapsed, allowing Manstein's forces to drive to Belgorod on 17 March, and take it by the next day. Muddy weather and exhaustion forced Manstein's counterstroke to end soon thereafter. The military historian Bevin Alexander wrote that the Third Battle of Kharkov was "the last great victory of German arms in the eastern front", while the military historian Robert Citino referred to the operation as "not a victory at all". Borrowing from a chapter title of the book Manstein by Mungo Melvin, Citino described the battle as a "brief glimpse of victory". According to Citino, the Donets Campaign was a successful counteroffensive against an overextended and overconfident enemy and did not amount to a strategic victory. Following the German success at Kharkov, Hitler was presented with two options. The first, known as the "backhand method" was to wait for the inevitable renewal of the Soviet offensive and conduct another operation similar to that of Kharkov – allowing the Red Army to take ground, extend itself and then counterattack and surround it. The second, or the "forehand method", encompassed a major German offensive by Army Groups South and Center against the protruding Kursk salient. Because of Hitler's obsession with preserving the front, he chose the "forehand method", which led to the Battle of Kursk. See also First Battle of Kharkov (1941) Second Battle of Kharkov (1942)