The former Liverpool boss believes that it is important to rest a host of players following their 1-1 draw with Sparta Prague, which placed them in the final 16 of the Europa League on Thursday.
"We have played around nine games a month, so we have played more games than anyone in Europe," Sky Sports News quotes Benitez as saying.
"When you play two games a week in two different competitions and you rest a few players and you win they will say 'fantastic rotation' but if you lose they say 'Why are you resting these players?'.
"We will change some of them against City, that is very clear because we have to do it and that is the way if you are a top side."
The Blues are currently third in the Premier League table.