Ole Gunnar Solskjaer’s side were humiliated at the hands of Everton yesterday, losing 4-0 at Goodison Park.
And Liverpool know if United can win the Manchester derby then the Premier League title could be on the verge of going to Anfield.
Van Dijk has called on United to react after their dismal showing against the Toffees.
“They need to do themselves a favour,” the Dutchman said.
“Everton is not easy to beat at home, but 4-0 is a big result.
“We have no influence on that, but they are still playing for Champions League football and they need to get a result.”
Liverpool ace James Milner has revealed he may not watch the crucial match though.
“I don’t watch them, to be honest,” he explained.
“It’s a bit of a waste of energy, isn’t it, willing the ball into the goal and things like that. I can’t do anything about it.
“Maybe I’ll put my phone away for a couple of hours and check it after.
“Maybe I’ll go and grab some food or whatever.”
And Milner has admitted it would be frustrating to lose out on the title after such a good campaign.
“I think for a long time we have had our head round the fact that we just need to win all of our games,” the former England midfielder added.
“And if we do that and it’s not good enough, you have to hold your hands up and say, ‘Well done City’.
“Of course it’s frustrating that we could have one defeat all season and it might still not be enough, but all we can do is win the rest of our games and keep putting them under pressure.”
Manchester United take on City at Old Trafford on Wednesday (8pm).