Manchester United's hopes of finishing among the top four in the English League took a huge dent on Sunday after they were hammered 4-0 away to Everton.
This means the Red Devils will have to put in an improved performance to beat City, who will be searching for key points as they look to defend their title.
"They need to do themselves a favour. Everton is not easy to beat at home, but 4-0 is a big result," said Van Dijk.
"We have no influence on that, but they are still playing for Champions League football and they need to get a result," he added.
Liverpool kept pace with City after a hard-fought 2-0 victory at Cardiff City on Sunday, but the Citizens will go above Liverpool if they win at United.
Virgil has however insisted that the team is concentrating on their matches, and will need to win the remaining three fixtures.
"We have three games left and we are going to try and win all of them. It’s going to be very hard, but that’s what we’re looking to do,"
The Merseyside club will next be in action at home against Huddersfield on Friday 26th.