Teraktorsazi came from behind to defeat Peykan 2-1 in Qazvin on Friday, a solo goal gained Foulad a home win against Malavan in Ahvaz, and Mes beat Saipa 1-0 in Kerman.
Rahman Rezaei scored for Peykan just three minutes into the game, and Mohammad-Hassan Ebrahimi and Mehdi Kiani were on target for Teraktorsazi.
Reza Norouzi scored for Foulad in the 70th minute, and Edinho scored the winner for Mes.
The two other games of the day ended in a draw when Steel Azin tied with Rah Ahan 2-2, and Shahrdari and Shahin were held with the same result.
In other matches of the week, Esteqlal will host Naft Abadan and Pas will meet Zob Ahan on Saturday.
Naft Tehran will take on Persepolis on Sunday, and Sepahan and Saba will play the last match of the week on Monday.
Defending champion Sepahan is still on top with a five-point gap with the second-placed Zob Ahan, which has 56 points. Esteqlal sits third on 55 points. Teraktorsazi is now fourth with 53 points.