"I'm over the moon to be back because it has been eight weeks of frustration as I could do everything but play," he said.
Now approaching his 33rd birthday, John scored 18 league goals in 70 appearances for Forest between 1999 and 2002."I have friends and family still in Nottingham and they gave me an opportunity to show what I can do with a football and I am grateful for that, but obviously I want to win," he added.
The Reds meanwhile have been fined £25,000 - of which £10,000 is suspended with Nathan Tyson handed a two-game suspended ban and a £5,000 fine for the after-match antics in the game against Derby in August.
The Rams, have been fined £20,000 -half of which is suspended.