Sayyiduna Anas (may Allah be pleased with him) narrates: On the occasion of the Battle of Hunayn, when the Muslims were routed, the Prophet (peace and blessings be upon him) was at that time riding his grey mule named Duldul. The Prophet (peace and blessings be upon him) said to it: "O Duldul, sit down." It pressed its belly to the ground, until the Prophet (peace and blessings be upon him) took a handful of dust and threw it toward those people. He said: "Ha Mim, they will not be helped." Then the enemy was routed, although we had not shot a single arrow at them, nor thrust a spear at them, nor struck them with a sword.
Al-Tabarani recorded it in al-Mu'jam al-Awsat. Its chain contains Ahmad bin Muhammad bin al-Qasim, who is da'if (weak).