It was his family ties that caused Uzun Hasan, Sultan of the Ak Koyunlu confederation, to hand over to him Abu Sa'id Mirza, whom he had defeated and captured at the Battle of Qarabagh in 1469.
Abu Sa'id, who had previously ordered the execution of Gawhar Shad, Yadigar Muhammad Mirza's great-grandmother, was subsequently killed.
Although Yadgar Muhammad Mirza was defeated by Husayn in battle in September, fresh reinforcements were sent by the Ak Koyunlu leader.
Eventually Husayn was compelled to evacuate Herat, which Yadgar Muhammad Mirza occupied in July 1470.
He was the last descendant of Shah Rukh to play a dominant role in the politics of the Timurid principalities.