An army under the supreme command of the Styrian general Ruprecht von Eggenberg was quickly assembled to break the siege. The Croatian troops were led by the Ban of Croatia, Thomas Erdődy, and major forces from the Duchy of Carniola and the Duchy of Carinthia were led by Andreas von Auersperg, nicknamed the "Carniolan Achilles". They made a surprise attack on the besieging forces on 22 June. The ensuing battle resulted in a crushing defeat for the regional Ottoman forces with Hasan killed, triggering the Long War.