Koptsov took command of the 46th Tank Division on the day after the German invasion of the Soviet Union began on 22 June. The division and its corps were transferred to the
Northwestern Front and unsuccessfully counterattacked at
Daugavpils on 25 June. The division fought in the retreat to the
Pskov area. During the
Baltic Operation Koptsov was wounded, but remained in command. On 31 August, Koptsov was awarded the
Order of the Red Banner. In September, the division was converted into the 6th Tank Brigade and transferred to the
7th Separate Army, fighting in battles against Finnish troops on the
Karelian Isthmus. On 11 September Koptsov was promoted to the rank of major general. Between November and December, the brigade fought in the Tikhvin Defensive and Offensive operations. During the Tikhvin Offensive Operation, the brigade was reported by Soviet sources to have killed 1,500 German soldiers and destroyed eight tanks, six armored vehicles, eleven guns, and large amounts of other military equipment. Koptsov was wounded again in the fighting and received a second Order of the Red Banner on 27 December. On 16 February 1942 the brigade was converted into the 7th Guards Tank Brigade for its actions. On 21 May Koptsov became commander of the 15th Tank Corps, part of the
3rd Tank Army. Aged 38, he was one of the youngest tank corps commanders at the time. In August 1942, the corps fought in the
counterattack against German troops at
Kozelsk. In 1943, Koptsov was awarded the
Order of Suvorov, 2nd class. From January 1943 the corps fought on the
Voronezh Front, fighting in the Ostrogozhsk–Rossosh Offensive. On the first day, 14 January, the corps attacked the XXIV Panzer Corps, overrunning its command post and killing its commander during a 20-kilometer advance. Operating in conjunction with the 12th Tank Corps, the 15th broke through German defenses and on 17 January closed the encirclement ring, linking up with troops from the
40th Army at
Alexeyevka. This cut off the retreat for the
Italian Alpini Corps and thousands of Hungarian and German troops. After the end of the offensive, the corps continued its advance against stiffening German resistance, suffering increasingly heavy losses. On 16 February it recaptured Kharkov. The corps fought in the Third Battle of Kharkov. On 23 February a German counterattack encircled a large Soviet force south of Kharkov. As a result, the 3rd Tank Army was ordered to relieve the trapped force, and the 15th Tank Corps was itself surrounded, defending a pocket around
Kegichevka. Koptsov ordered his remaining troops to break out, and he was seriously wounded on 28 February. ==Death==