After Lord Methuen attempted to relieve the siege of Kimberley, Cronjé fought the Battle of Modder River on 28 November 1899, where the British won a Pyrrhic victory over the Boers. Cronjé's novel tactics at the Modder River, where his infantry were positioned at the base of the hills instead of at the tops—to increase the effectiveness of their rifles' flat trajectories—earned him a place in military history. However the tactics ascribed to him were not his own; he was convinced by General Koos de la Rey and President Martinus Theunis Steyn. After Modder River, Cronjé repulsed Methuen's forces at the Battle of Magersfontein on 11 December. This was actually due to 's tactics and planning; Cronjé sat idle in camp.