He is only seen before a German attack on the Soviet line in the level "Demolition". After figuring out that the German soldiers barricaded themselves on the upper floors, he orders the destruction of the German building using TNT, denying a Soviet soldier's request to ask the Germans to surrender. The engineers and the player must plant enough explosives on the main supports to knock down the building. After they set the charges, they all run as quickly as possible to a safe distance to avoid the blast. Though the dust and smoke makes them all cough, they managed to successfully get to a safe distance. He is not mentioned nor seen in the game again after the destruction of the German outpost. He is replaced by Dimitri Volsky for the remainder of the Russian Campaign.
- "I'll ask them when I've blown them to hell! Get the explosives up here now!"
- — Leonov in response to being asked if they should ask the Germans for their surrender
- "That's how you negotiate with fascists comrades!"
- — After destroying the German outpost