In the match held in Tabriz, Domagoj Drozdek scored three goals in the first half and Behrouz Norouzifard pulled a goal back just before the break.
Tractor’s Albanian forward Regi Lushkja made the scoreboard 4-1 just after the hour mark.
Later in the day, Esteghlal lost to Esteghlal Khuzestan 1-0 at the Foolad Arena in Ahvaz. Mohammad Sharifi scored the sole goal in the 34th minute.
Kheybar Khorramabad and Fajr Sepasi shared the spoils in a 1-1 draw, while Gol Gohar drew 1-1 with Sepahan in Sirjan.
Persepolis will meet Foolad in Tehran on Saturday, Shams Azar host Paykan, Zob Ahan face Mes Rafsanjan in Isfahan and Chadormalou play Malavan in Yazd.