On 25 June 1941, JG 53 was relocated with III. "Gruppe" arriving at Vilnius at 8:30 am. The same day, Wilcke was slightly injured when he collided with another aircraft during takeoff. He claimed his 19th victory on the evening of 30 June 1941, flying a combat air patrol into the Barysaw area. Wilcke was ordered to form ""Gefechtsverband Wilcke"" ("Battle Group Wilcke") on 1 July 1941. He commanded his III. "Gruppe" and II. "Gruppe" of "Jagdgeschwader" 52 (JG 52—52nd Fighter Wing) to counter-attack Soviet bombers. On 9 July, Wilcke destroyed a Petlyakov Pe-2 ground attack aircraft. He claimed a victory on 25 July during fighter escort missions in the Vyazma area. On 29 July 1941, III. "Gruppe" provided fighter cover for the German armored spearheads in the Dukhovshchina area. During this mission, Wilcke claimed another victory. The next day, over the spearheads at Yartsevo-Bely, Wilcke shot down a Polikarpov I-180 fighter. He was awarded the Knight's Cross of the Iron Cross () on 6 August 1941 for 25 victories. Both Wilcke and "Leutnant" Herbert Schramm were decorated by Kesselring on 9 August 1941.