In April, Popov was appointed commander of the 33rd Guards Rifle Corps, which became part of the 5th Guards Army of the Steppe Military District in July. He led the corps in the Battle of Kursk, during which it fought alongside the 32nd Guards Rifle Corps of the army in heavy defensive battles in the Psel in the region of Oboyan, halting the advance of the 1st SS Panzer Division Leibstandarte SS Adolf Hitler. The division then fought in the counterattack of the front in the Battle of Prokhorovka, During these actions, Popov demonstrated "heroism, courage, and firmness" in directing the units of the corps.