The two rivals meet at Old Trafford on Saturday in a game the visitors must win.
Liverpool are seven points behind United and the Red Devils also have a game in hand.
“I think we’re in pole position anyway, but we can certainly end Liverpool’s chances of winning the league if we win, so we’re looking forward to it,” Rooney told Sky Sports News.
Rooney refuses to get carried away by talk of ligting five trophies this season.
He added: “We always try and win every tournament we go into at the start of the season.
“We’re in all the competitions, but we know there is a long way to go in the season, and we know that we just have to keep focused and try and do the best we can.”
