FA Cup semi to League rivals in 1day?

I'm Man United and have just been playing vs Man City in the FA Cup semi and i've played my first and best team as City have thrown their wallet at the league and finsh in the top 4 most seasons so they are a hard team. I just won 2-1

Then the next day under 24 hours were playing Chelsea who are in 2nd behind by 2 points with a game inhand so who wins will be in the front seat for the title. My team is 70-85 fitness so my youth will be playing which will be fun. :o