The 23-year-old is widely considered to be on of the very best stoppers in English football outside of the top tier, and was a top performer for the Tricky Trees last season.
A number of top clubs are rumoured to be watching his development closely, with Arsenal in the hunt.
The Gunners recently lost FA Cup Final hero Lukasz Fabianski on a free transfer to Swansea, and are known to be looking for a back-up man to challenge Wojciech Szczesny for the No 1. spot.
World Cup stars Keylor Navas and Guillermo Ochoa are favourites among the tabloids, but it is understood that Darlow is a top target for Arsene Wenger.
The Frenchman is said to have been impressed by his showings in the second tier, and is confident that he could make the step up.
Forest are, naturally, reluctant to sell their star, but the cash that could be brought in – likely to be around £5m-£7m – would help manager Stuart Pearce build a squad capable of mounting a charge for promotion.