Mahmoud Fekri’s team overtook its host at top of the table with a 2-1 win in Sirjan.
Vouria Ghafouri was on target from the penalty spot in the 8th minute and Mehdi Ghaedi scored Esteghlal’s second goal six minutes later.
Ahmad Reza Zendehrooh pulled a goal back from the penalty spot in the 78th minute.
In Tabriz, Tractor was held to a goalless draw against Shahr Khodro and Paykan defeated Naft Masjed Soleyman thanks to Farzad Hatami’s 82nd-minute goal.
Foolad also beat Nassaji 1-0 in Ahvaz. Ayanda Patosi scored the solitary goal of the match in the 16th minute.