 Following the collapse of Umayyad rule in Iraq and Khurasan in 683–684, during the Second Muslim Civil War, al-Muhallab was pressed by the Basran troops to lead the campaign against the Azariqa, a Kharijite faction which had taken over Ahwaz and threatened Basra.Al-Muhallab landed them a severe blow and drove them into Fars in 685.He was rewarded with the governorship of that province by the anti-Umayyad caliph Abd Allah ibn al-Zubayr (), whose suzerainty had been recognized in Basra in the wake of the Umayyads' ouster.