In 1759, Kleist became chief of Regiment Szekely, also called the Greens (due to the dominant color of their uniforms), a position he held until his death; hence forth he was also known as "Green Kleist". In 1760 Kleist was promoted to the rank of colonel. On 15 August 1760, the Kleist Hussars played an essential role in the Battle of Leignitz. At a point when the outcome was in the balance, 14 full squadrons of Kleist cavalry hit the enemy cavalry; the latter fled and the Prussians took the battlefield.