Roberto Firmino scored in the 32nd minute put Liverpool up 3-0. Getty

Liverpool scored three first-half goals to stun Manchester City on Saturday night at the Etihad Stadium, 4-1. Coupled with Arsenal's loss to West Bromwich Albion, the improbable Premier League leader after 13 matches are Leicester City, with City even with their local rivals Manchester United for second place.

It was a painful home performance for Manuel Pellegrini's squad. A clumsy effort from City defender Eliaquim Mangala, in the wrong place at the wrong time, resulted in an own-goal in the seventh minute to put Liverpool up, but the Reds were just getting started. Liverpool were able to cut through the City defense in the 23rd minute, as Roberto Firmino did an excellent job of finding central midfielder Phillipe Coutinho, who delivered a one-time shot from close range past Joe Hart.

Jurgen Klopp's side would continue their onslaught with more exceptional passing. A backheel from Emre Can helped set up an assist from Coutinho to his fellow Brazilian Firmino that put the Merseysiders up for good, 3-0.

But just before the break, City star forward Sergio Aguero proved his fitness with a stunning right-footed blast from beyond the box that Simon Mignolet could nothing about. Aguero had been sidelined for six weeks with a hamstring tear and had recently missed international duty with Argentina.

Liverpool would earn their final goal in the 81st minute when Adam Lallana's corner kick was headed by Christian Benteke, and dropped for Martin Skrtel, who pounced on the loose ball with a powerful shot from distance to add to Hart's frustrations.

Up next for Liverpool is a Europa League match against Bordeaux on Thursday at Anfield, while City travel to Turin for a road match against Juventus in Champions League group play.

0-1 Eliaquim Mangala Incredible Own EarthSavii

Philippe Coutinho 0:2 | Manchester footballTV

0-3 Roberto Firmino Goal | Manchester City EarthSavii

Kun Aguero 1:3 Amazing Goal | Manchester City... by EuropeanLeagueLiveGoal

Skrtel Goal - Manchester City 1-4 Gol-Live