Jamie Carragher has warned Manchester Untied that Liverpool now have the mental strength to mount a serious assault on the Premier League title.
United's back-to-back league defeats against Liverpool and Fulham, and the Anfield club's demolition of Aston Villa, has seen the reigning champions' lead over second-place Liverpool cut from seven points to just one.
''United will realise they are in a fight for the league now. We're the form team, and this is the best time of the season to be in form,'' Carragher said.
"There's not long to go now and hopefully we can keep it going - but United will know now that we are in there.
''Earlier in the season, we hadn't been at the top before and we didn't know how to deal with it. But we are maturing and getting used to the demands of fighting for a title,'' added the 31-year-old.
Liverpool's form and morale could not be higher after stunning wins in the league, Rafa Benitez finally agreeing a new contract and the recent Champions League win over Real Madrid.
However, Carragher knows United remain favourites to lift the Premier League for a third season in succession because of their vital game in hand.
''One point with a game in hand is a decent lead. We've just got to stay on their coat-tails,'' added the central defender.