The Reds suffered a disappointing 2-1 loss in the French capital to deal a blow to their hopes of reaching the knockout stage of the Champions League.
The defeat has left Jurgen Klopp’s men in third place in their group – two points behind PSG and three points behind leaders Napoli.
Liverpool FC will host Napoli in their final crunch clash in the Champions League group stage at Anfield on 11 December as they look to claim the three points to give themselves a chance of reaching the last 16.
To qualify for the last 16, Liverpool FC must beat Napoli either 1-0 or by two clear goals in front of their home fans.
And Van Dijk has told his Liverpool FC team-mates that they must make sure that they are at their best for that crunch clash on Merseyside.
Speaking to Liverpool FC’s website after Wednesday night’s defeat, Van Dijk said: “Yes, that [the game against Napoli] is the only thing that’s left.
“We need to be up for it and we will be. We need everyone for that and I’m not in doubt that’s going to happen.
“Everyone is going to be ready for it. Until then, we need to be ready for the league as well and win our games.”
Liverpool FC will first turn their attentions back to the Premier League and their Merseyside derby clash against Everton at the weekend.
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