Liverpool are four points behind leaders Chelsea with a match in hand, ahead of Arsenal on goal difference and two points in front of Manchester City, although Manuel Pellegrini's side have played two matches fewer.
"I think they are going to be worried," said Flanagan. "We put a marker down (at Old Trafford). I think we are ready to push on and keep going.
"We all believe but our priority was top four at the start of the season. We are on track for that and anything else is a bonus.
"We are just taking it a game at a time and keeping our feet on the ground."
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