When the pro-Umayyad Arab tribal nobility of Syria, chief among them the chieftain of Banu Kalb, elected Marwan ibn al-Hakam as caliph at the Jabiya summit of 684, it was stipulated that Yazid's then-young son Khalid would succeed Marwan, followed by al-Ashdaq. The latter commanded the right wing of Marwan's army during the Battle of Marj Rahit later that year, in which the Umayyads scored a resounding victory over the pro-Zubayrid Qaysi tribes of Syria. During Marwan's expedition to wrest control of Egypt from its Zubayrid governor in 685, al-Ashdaq was present and delivered an address proclaiming Marwan's sovereignty from the pulpit of the mosque in Fustat. Afterward, al-Ashdaq was dispatched by Marwan to stave off an invasion of Palestine by Mus'ab ibn al-Zubayr, who was attempting to conquer Umayyad Syria during Marwan's absence. He then joined Marwan and took up residence in the Umayyad capital of Damascus. The caliph remained wary of al-Ashdaq's ambitions to the caliphate, particularly due to his popularity among the Syrian Arab nobility and his close kinship to Marwan, who was his maternal uncle and paternal relative as well. Marwan resolved to avoid the potential leadership bids of al-Ashdaq and Khalid by having his sons Abd al-Malik and Abd al-Aziz, in that order, recognized by the Syrian nobility as his chosen successors.