24-year-old Etemadi had started his career in the Netherlands at Heerenveen before signing with Groningen after short spells with Emmen and Veendam.
However, the Tehran-born son of an Iranian father and Dutch mother wasn't happy with his reserve keeper role and decided to increase his chances to receive a Team Melli call-up by transferring to Iran.
The former Netherlands U21 player repeatedly announced his willingness to play for Iran one day, such as in an interview with Persianfootball.com four years ago.
"It would be a dream to wear Iran's jersey and perhaps represent Iran some day at a World Cup", Etemadi told Persianfootball.com in 2007 while also naming Ali Karimi and Andranik Teymourian as his favourite Iranian players and World Cup 1998 goalkeeper Ahmad Abedzadeh as best Iranian goalkeeper ever.
Tractor Sazi, currently fourth in the table trailing IPL leaders Esteghlal by seven points, just reseased goalkeeper Abbas Mohammadi but also signed Iran playmaker Ghasem Hadadifar of Zob Ahan and Olympic team rightback Milad Fakhreddini of Mes Kerman.
Both players joined Amir Ghalenoei's squad due to military conscription.
Only a handful clubs in Iran, such as Teractor Sazi Tabriz, Malavan Anzali or Fajr Sepasi Shiraz, are connected to some sort of military branch and are therefore allowed to employ players during their mandatory two-year military service.