The champions are five points behind leaders Chelsea, who have a game in hand, having missed the chance to cut the gap in defeat to Liverpool over the weekend.
However, City once again left themselves too open and exposed their lack of pace and energy as they failed to learn from the mistakes that they made against Barcelona in the Champions League only five days earlier.
Their 2-1 home defeat to the Spanish giants and their setback on Merseyside leave the Citizens facing the very realistic possibility that they end the season trophyless, although Pellegrini may be able to take respite in their upcoming fixtures.
City follow up their match against the bottom-of-the-table Foxes with a trip to relegation-threatened Burnley and games against West Bromwich Albion and Crystal Palace, so will expect to still be in the title race come April.
Leicester are fighting on a completely different front and are at risk of being cut adrift after picking up just one point from a possible 15 - a 2-2 draw against Everton in which they were denied victory by a late own goal.
Nigel Pearson's side had the weekend off and so an unchanged side could head refreshed to the Etihad Stadium for the reverse of December's tightly-contested encounter in which Frank Lampard's goal was enough for City.
The visitors have shown that they will not roll over for the top sides - they are yet to lose by greater than a two-goal margin this season - and will be hoping that the luck that has eluded them at times could help towards another famous Manchester scalp.
The experience of the fit-again Matthew Upson and January signing Robert Huth will be valuable in their newly-adopted back five, behind whom Mark Schwarzer will continue to deputise for the recovering Kasper Schmeichel.
David Nugent and Jamie Vardy both made an impact as substitutes against the Toffees, but may have to settle for places on the bench again as Pearson keeps faith with £10m club-record buy Andrej Kramaric in attack.
Pellegrini's 4-4-2 formation has worked perfectly well against the division's lesser sides and therefore the City boss could again partner Sergio Aguero with Edin Dzeko, although Wilfried Bony is pushing for a full debut.
The inclusion of the Ivorian, who arrived from Swansea City for £26m in the winter transfer window, could be the only City change, with Fernandinho anchoring a midfield also consisting of Yaya Toure, David Silva and Samir Nasri.
Form in Premier League: LDDWWL
Form in all competitions: DDWWLL
Possible starting lineup: Hart; Zabaleta, Kompany, Mangala, Kolarov; Nasri, Toure, Fernandinho, Silva; Aguero, Bony
Form in Premier League: WLLLLD
Form in all competitions: WLLLLD
Possible starting lineup: Schwarzer; Simpson, Morgan, Huth, Upson; Konchesky; Mahrez, James, Cambiasso, Schlupp; Kramaric
Sports Mole says: 2-1