The ground offensive for Kerch opened on 8 May but almost immediately, III./JG 52 (with Graf on 90 victories) was sent back to Kharkov, to counter a major Soviet offensive there. The air conflict was intense and in the first two days (13–14 May 1942), Graf shot down thirteen aircraft, which included his 100th victory. He became the seventh "Luftwaffe" pilot to achieve that milestone. It is an illustration of his dominance within his "Gruppe", and the "Luftwaffe" tactical doctrine of ace versus wingman. In the first six months of 1942 Graf alone accounted for a quarter of all the aircraft shot down by III./ JG 52 It was the culmination of a remarkable seventeen days since his return to the front in which he had shot down 47 aircraft. He was awarded the Oak Leaves to the Knight's Cross on 17 May 1942 for achieving 104 victories. Only two days later, his score now at 106, he was notified that he was also to receive the Swords to his Knight's Cross. On 24 May, Graf and "Leutnant" Adolf Dickfeld of 7./JG 52, flew to the Eastern Front headquarters at Rastenburg in Poland (the Wolf's Lair), for the official Oak Leaves and Swords presentation by Adolf Hitler the next day. Dickfeld was presented with the Oakleaves, having been awarded it on 19 May for achieving 101 victories after he shot down eleven aircraft on 18 May.