In the match held in Isfahan’s Fooladshahr Stadium, Persepolis was reduced to 10 men in the 20th minute after referee Yadollah Jahanbazi showed a straight red card to Persepolis keeper Iman Sadeghi.
The referee believed that Sadeghi touched the ball with hands outside the penalty area but the TV replays showed that the ball touched his chest.
Morteza Tabrizi scored Zob Ahan’s first goal in the 105th minute and substitute Reza Shekari made it 2-0 eight minutes later.
Zob Ahan qualified for the semi-final and will play the winner of Sepahan and Rah Ahan.
Elsewhere, Esteghlal defeated Foolad 3-1 in the Round of 16.
Esmaeil Sharifat gave the visiting team a lead just after three minutes.
Meysam Majidi equalized the match in the 15th minute. Hanif Omranzadeh made it 2-1 for Esteghlal in the 20th minute and Jaber Ansari scored the third goal in the 77th minute.
Naft defeated Padidieh 4-2 in penalty shootout and advanced to the quarterfinals.
Saipa lost to Tractor Sazi 2-1 in this stage.