Jurgen Klopp’s men ran riot at the Etihad as the Reds’ high intensity pressing game forced Manuel Pellegrini’s side into submission, and the display was arguably the best Liverpool have played since they hammered Arsenal 5-1 at Anfield back in February 2014.
Strikes from Philippe Coutinho, Roberto Firmino and Martin Skrtel went a long way to securing the points at the Etihad, despite a wonderful effort from Sergio Aguero, but it was an own goal from Eliaquim Mangala that got the Reds in business early on in Manchester .
Injury ruled Vincent Kompany out at the Etihad, and manager Pellegrini opted to partner Mangala alongside Martin Demichelis, but neither defender looked comfortable against the trio of Adam Lallana, Coutinho and Firmino.
City simply had no answer for Klopp’s approach and Keown, who was known for his uncompromising defending during his playing days with the Gunners, was thoroughly unimpressed with how the Premier League title favourites defended against the high octane Liverpool.
Keown told BBC Sport: “As good as Liverpool were, I thought Manchester City let themselves down.
"They brought in Mangala and Demichelis for Kompany and Otamendi and it was comical, it was comical defending at times.
“The two central defenders put their side into trouble. It was almost like a practice game in the early stages. It was so sloppy and they didn’t do their jobs properly.
“Liverpool just ran through midfield and it really was embarrassing for City.”
Bacary Sagna and Aleksandar Kolarov made up the rest of the back four, but the former has since admitted that he was not in the right frame of mind to play after the terrorist attacks in his native France on October 13.
Fabian Delph and Fernandinho were brought in for Jesus Navas and Yaya Toure respectively at half time, but the midfielders did little stem the tide, and City had goalkeeper Joe Hart to thank for keeping the score down in front of their own crowd.
The England international denied Firmino either side of the break before thwarting Benteke just before Skrtel rattled in a fourth late on, and City know they will need to improve if they want to wrestle back the title they last won in 2014.
Pellegrini’s men return to action this week when they face the daunting task of travelling to Juventus in the Champions League.