Darren Fletcher is warning United against the dangers of the wounded Liverpool animal. The Merseysiders are licking their wounds having been ousted from a three-way Premier League title race between the Reds, Chelsea and Arsenal. The final member of the so-called English Big Four are now scrapping for a Champions League lifeline. Rafa Benitez's side took the Reds to the wire last term in the race for the crown thanks to a stunning 4-1 Old Trafford win - 12 months ago last weekend. Sir Alex Ferguson's champions held off the challenge but this season Liverpool have collapsed as a force both at home and abroad. However, Fletcher insists Liverpool can still upset United's apple-cart. "It would be very dangerous to think this is a poor Liverpool side coming to Old Trafford because they will be anything but," the Scottish midfielder told MEN Sport. "It would be a huge mistake to think that Liverpool aren't a threat. They maybe haven't had the season we expected after the one they had last year but they are still a dangerous side. "They are still the same team they were last year in the main. We know what they are capable of because they pushed us all the way and dished out that defeat here and the one at Anfield this season. They are still fresh in our memories. "They still have a lot to play for because they are battling for fourth spot. On their day they are capable of beating anyone. "We have to learn the lessons from last year's game. The warnings are there. If you are not 100 per cent focused and you make mistakes then Liverpool will punish you. "After last season everyone thought they would kick-on this year and would be right up there again. A lot of people tipped them to win the league. It hasn't turned out that way for whatever reason. "It is a real surprise to me they haven't been up with us. But they'll still be fired up to win at Old Trafford again. "Last March's defeat was difficult to swallow at the time. We were in the middle of the run-in and to lose against Liverpool, who were challenging us and especially at home, was tough. "It is not about revenge. It is simply about the match and the title run-in."