Boss Steve Cooper has warned Manchester City his Nottingham Forest stars have learned from their mistakes.
Forest host the Premier League leaders on Saturday and are unbeaten at the City Ground in the top flight since September.
They lost 6-0 at City in August but have beaten Liverpool and Tottenham at home, while also drawing with Chelsea since, and Cooper knows they have improved.
He said: “That was at the start of a bad run and there were some things in those games that were real standouts for us that we had to change and we’re still changing and working on stuff.
“We’ve had some forward steps and some backwards ones as well.
“It’s going to be a real game for concentration and mentality and you can find in games you tire physically but you need to ensure you don’t tire mentally. We have to really stand up to that.”
Steve Cook could be available after Forest asked the Premier League for special dispensation to recall him to their 25-man squad.
Cooper wants the defender back to plug the gap after Willy Boly was ruled out for the rest of the season with a hamstring injury and Scott McKenna is also sidelined for six weeks.
Forest are six points above the relegation zone and Cooper knows City must be respected but not to his side’s detriment.
“There is that risk and you have to get the balance right between recognising who they are and what they can do but recognising yourself as well,” he said.
“Football is a competition and you have to compete in every way. If we don’t do that and we’ve learnt that at times this year. There’s less room for error in this league, you have to get the balance right and I hope we do.
“We know we have to build our stuff on togetherness and spirit.
“I’ve been part of a couple of successful teams now with England and Swansea and last year at Forest. The common denominator when things go well is a strong spirit so that’s always the aim.
“There’s been a lot more work focusing on that this year because there’s so many new players and there’s a step up in league and the demands. I don’t know if siege mentality is the word but really sticking together and having the greater good of the club in mind.”