Liverpool boss Jurgen Klopp said his side's capitulation in the 4-1 Premier League loss to Manchester City at Etihad Stadium was simply "not acceptable".
Last season this was a tantalising, high-stakes fixture between two title rivals, but on Saturday it proved to be a one-sided thumping, with City's dominance highlighting the gulf between the sides.
Liverpool opened the scoring when Mohamed Salah finished off a counter-attack in the 17th minute but Julian Alvarez equalised 10 minutes later before Kevin de Bruyne, Ilkay Gundogan and Jack Grealish added second-half goals to complete the rout.
As City hunt a third consecutive league title, Liverpool are seven points adrift of the Champions League places in eighth and former Manchester United defender Rio Ferdinand says it is "worrying times" for the Reds.