The Tigers are in the relegation zone, but damaged Liverpool's Premier League title chances with goals from Senegalese duo Oumar Niasse and Alfred N'Diaye at the KCOM Stadium.
"At this moment obviously that was not enough," he told reporters. "We gave both goals away easily, the overall performance was not like it should be. It makes no sense for us to play like this.
"If we played like we did in the second half for the whole game no team can cope with us. But we need to wake up, that was not acceptable.
"I have a lot of thoughts at the moment and I can't even say a few of them right now because I really need to think about what happened."
— LFC Photo (@LFCphoto) February 4, 2017