Jurgen Klopp admitted that Liverpool's weaknesses were laid bare to their Premier League rivals as they lost 2-0 in the Champions League at Red Star Belgrade.
Milan Pavkov's first-half brace condemned Klopp's men to a result that contrasted starkly with their 4-0 win over the same side two weeks earlier, the Reds squandering the chance to strengthen their hold on Group C.
With rock-bottom Fulham heading to Anfield in the top flight on Sunday, Klopp said his players would need to reflect on their mistakes to ensure an improved performance as they seek to extend their unbeaten run in domestic action.
"[We have] A long flight home, a long time to think, and then Sunday Fulham are waiting," Klopp told BT Sport.
"They saw the game probably and will be thinking 'okay, this team has weaknesses'.
"So we have to not show them anymore on Sunday."
Liverpool's forwards failed to take opportunities that Klopp claimed they would normally expect to score, and the German coach picked out chances that fell to Sadio Mane and Mohamed Salah as being significant misses.
He hinted at defensive problems being to blame for Pavkov's goals, which arrived inside seven first-half minutes.
"Of course you could see that a few things are not going too well," said Klopp. "They had chances, but we had chances that we usually score with.
"They defended on the line twice, but they had too many set-pieces and with one of them they scored, and then out of the blue they more or less score the second one.
"And then the atmosphere was completely different, you could feel it. They were on their bikes and we had to deal with the situation.
"At half-time we tried to change a few things and the second half was really dominant, but we didn't score.
"We had the situations of Sadio [Mane], Mo [Salah], big chances, a lot of ones that won't count as a shot on target because we missed.
"If we score one of them the game changes but we didn't. We were fighting hard, but they deserved the three points."
Klopp stopped short of offering a detailed explanation for a performance that paled in comparison to their recent Premier League displays, and expressed belief in his players to make amends for the defeat.
"I am a human being," he said. "If 10 minutes after the game here I have a big speech I will look a bit silly.
"We will go for the other two games 100 per cent, but I have no message in the moment, we all have to deal with it.
"It was a game we lost, we feel it, the boys are disappointed, I am disappointed, and we have to do better, because we can do better, but tonight it's too late, we have to learn."