Jalal ad-Din positioned his army of at least thirty thousand men in a defensive stance against the Mongols, placing one flank against the mountains while his other flank was covered by a river bend.The initial Mongol charge that opened the battle was beaten back. Jalal al-Din counterattacked, and nearly breached the center of the Mongol army. Genghis then sent a contingent of 10,000 men around the mountain to flank Jalal ad-Din's army. With his army attacked from two directions and collapsing into chaos, Jalal al-Din fled across the Indus river.