"I was watching the game and there was not one second where I was rubbing my hands together," Jurgen Klopp told a press conference when asked to rate Man United's performance against Atalanta.
"Even in the first half, United had three clearcut chances. Second half was demonstration of United going for it which can cause problems.
"We all know how the football world is. United/Liverpool is a massive game," the German added.
"Man Utd are not overly happy with their results but they are able to do incredible stuff. We will focus on ourselves."
Klopp's words are a reference to Paul Scholes' rant after Man United's Champions League game.
United are approaching this Sunday's clash in a bright mood, having completed a comeback to defeat Atalanta 3-2 - but Liverpool should present an even tougher challenge.
