Mohammad Reza Khalatbari scored the all-important goal for Zob Ahan three minutes before the half hour mark.
Mansour Ebrahimzadeh’s will host defending Asian champions Korea Republic’s Pohang Steelers in the first leg of their ACL quarter-finals on September 15 before travelling to Pohang for the return leg a week later.
Zob Ahan are on 13 points, three more than second-placed Pas.
In other matches, Esteghlal blanked Peykan 3-0, Malavan lost to Saipa 3-2, Steel Azin were held 1-1 by Mes, Pas played a 1-1 draw with Naft, Shahin drew goalless with Teraktor and Foolad held Saba Battery goalless.
