The European and Premier League champions go head-to-head at Wembley this Sunday with a place in the FA Cup final up for grabs.
Chelsea and Manchester City have had an inconsistent season where the domestic league is concerned, as the Blues are striving to secure Champions League football for next season, while their North-West opponents are poised to lose their league title to Manchester United.
Despite concerns over their league campaigns, both sides can finish the season with silverware, but only one will be able to contest for the FA Cup trophy either against Millwall or Wigan Athletic.
Chelsea may head into the clash as slight favourites due to their status as the competition's current holders, but a battling Europa League clash against Rubin Kazan in Russia could leave the Blues with tired legs.
Chelsea interim boss Rafael Benitez is expected to ring the changes for this weekend's match, bringing Oscar, Eden Hazard and Juan Mata back into the fold, while John Terry is likely to drop to the bench.
Meanwhile, Mancini has revealed today that he will hand playmaker David Silva a late fitness test on a hamstring strain, but the Spaniard is unlikely to start the game even if he is declared fit to be in the squad.
While a goalless draw and a 2-0 victory for Man City have materialised between the two clubs in the league this season, a cup tie is always a different story.
Manchester City: WWLWW
Possible starting lineups
Chelsea: Cech; Azpilicueta, Ivanovic, Luiz, Bertrand; Ramires, Mikel; Hazard, Oscar, Mata; Torres
Manchester City: Hart; Zabaleta, Kompany, Nastasic, Clichy; Toure, Barry; Milner, Tevez, Nasri; Aguero
Sports Mole says: 1-2