Liverpool were 4-0 up over Crystal Palace and in cruise control when Sadio Mane, who scored the second goal, had his name called to be substituted just before the hour mark.
But the Senegalese star's disapproval was clear as he initially ignored his number on the board and resisting the change before eventually giving in and making his way to the dugout.
Mane was spoken to by team-mates Roberto Firmino and Takumi Minamino before making his way off.
He high-fived both Klopp and the incoming Salah but did not say a word before making his way to the stands to watch the rest of the game.
Jurgen Klopp addressed the incident after the game and played it down as a human reaction.
Klopp told BT Sport: “He was not angry because Mo came on.
“He was not happy because he had a look at the watch, maybe it was the free-kick I don't know exactly. He didn't stay on the pitch until after the free-kick.
“So the boys, you cannot play football like this if you are just a soldier and do everything what the boss is saying.
“They do what I say but they are human beings and react in certain ways. After the game Sadio was completely fine. It's all good.”
This article was most recently revised and updated 2 years ago