That is indeed a crucial match for both teams but more for Nottingham Forest. If Nottingham Forest succeeds in qualifying for champions league next season, that will be a big achievement for them, that is why they need to win as many matches as possible. The champions league spot is still a very big fight between Manchester City, Nottingham Forest and Newcastle but just like you said, Chelsea have a very high chance of beating Leicester to enter the third position depending on what the outcome of Nottingham Forest against Manchester City is as either of them that wins the match will be third.
After enjoying Nottingham Forest's match against Arsenal, I feel like Nottingham Forest might get points from this match as well. But this match at Manchester City and Nottingham Forest can be much more important. It should be noted that Manchester City has won very well in the FA Cup, in fact they will try to win the trophy there by scoring three goals in that match. So my idea is that if the Nottingham Forest can strengthen their defense then the most difficult thing for the city will be. Yet I am convinced that the Nottingham Forest will not play bad in the next match.
Well, The match between Nottingham forest and Manchester city that is coming up is definitely more important than the match Nottingham played against Arsenal a couple of days ago that ended in a goaless draw.
Reason for this is because, Nottingham forest and Manchester city seems to be dragging position at the moment, Nottingham forest is in the 3rd position with 48 points while Manchester city is in the 4th position with 47 points, just 1 point difference.
And what this means is that if Nottingham forest wins that match they get to keep their 3rd position and also increase by 3 points..
But if Manchester city wins the match, they will move up to the 3rd position while Nottingham forest will slide down to the 4th position, the battle will be intense I believe, and this is one of the matches I really look forward to seeing.