It will be depending on the winning score because even if Manchester United win the match, it does not guarantee that they will take the 5th position from Arsenal since the points will be the same and Arsenal is having better goal difference now (+8) while Manchester United +3 only.
Sorry, I've just realized that I typed Arsenal instead of Tottenham. In case Manchester United become victorious tonight, they will leave Tottenham behind. They have a chance for the fifth position in the standings also but it doesn't seem realistic to me. Because there is a big goal average difference between Arsenal and Manchester United as you said also and I don't wait for Manchester United to destroy their opponent by a gap like that. Manchester United should be thankful even if they win this somehow as they are having difficult times lately.