Daws was hoping to rematch Di Rocco following a controversial loss to the Italian in June 2013 as Londoner, 36, claimed a yellow substance was used to treat an injury suffered by the then title holder – which is against corner rules.
That fight looks destined not to happen though as Di Rocco concentrates on a potential world title fight and Daws aims to finally claim the blue belt that has eluded him for years.
Forthcoming opponent Nieto was also defeated by Di Rocco when the pair fought out a twelve rounder last October but the 32 year-old has since put himself in a mandatory position with a low-key win over journeyman Zoltan Horvath.
Both fighters have won national and EU honours in their careers, but will hope to make that final step up towards world level and be challenging to the top contenders in the near future.
Purse bids have been stipulated by the EBU to take place on September 10 for the contest which gives representatives a couple of weeks to prepare their offers.