The 23-year-old custodian canceled his contract with the Blues on Monday and penned a one-year contract with Shams Azar.
Rezaei had no chance of playing in Esteghlal because he was the third option after Hossein Hosseini and Mohammad Reza Khaledabadi.
He had joined Esteghlal from Paykan in 2021.
Shams Azar sits at the bottom of the table in the Iran Professional League (IPL).