The more I think about this match, the more I think that City need to go as strong as possible.
Chelsea are under pressure from West Ham, Spurs, and the Dippers for the Champions League place. They are three points ahead of West Ham, five ahead of Spurs and seven ahead of Liverpool, who have an extra match.
Lose to City and West Ham could be breathing down their neck. After playing City, Chelsea face Arsenal, Leicester twice (once in the FA Cup), and Villa before the CL Final. Lose to City and they will be forced to go strong every match. West Ham have a considerably easier run-in with Everton, Brighton, West Brom and Southampton.
If City play silly buggers with a weakened team v Chelsea, will potentially take the pressure off them. That might allow them to rotate in their last two matches.