After a month awaiting assignment, Gryaznov became commander of the 14th Guards Rifle Division on 23 June. Between August and October 1942 he led the division as part of the 63rd Army in the defensive phase of the Battle of Stalingrad. The division subsequently fought in Operation Uranus and Operation Little Saturn as part of the 21st Army and the 1st and 3rd Guards Armies of the Southwestern Front during late 1942 and early 1943. After serving temporarily commanding the 14th Rifle Corps from 24 December, Gryaznov was appointed commander of the 15th Rifle Corps on 15 January 1943. He led it as part of the 6th Army of the Southwestern Front in Operation Gallop, during which it captured Kupyansk and Balakleya. Injured in a car accident on 28 March, he was evacuated to a hospital in Moscow.