Chelsea came from a goal behind courtesy of a Frank Lampard penalty to beat Manchester United to give the chasing pack a massive oppurtunity.
Both teams started with attacking formations and it was clear in the first few minutes that both sides were going all out for the victory.
Fernando Torres had the ball in the back of the net after just two minutes, although he had shot after the referee had blown his whistle.
Manchester United dominated the early possession of the game and were asking questions before the half hour and took the lead through Wayne Rooney right on the half hour.
Nani picked up the ball outside the Chelsea penalty box before playing the ball to Rooney, who looked up and Fired home from outside the box.
United looked good for their lead and went it 1-0 at the break looking good from their performance.
Ancelotti will have reminded his players of the need for a result against United, and whatever he said at half time worked as his Chelsea side came out roaring in the second half.
Chelsea knocked and knocked on United’s door and totally over ran Carrick and Scholes in midfield before David Luiz fired home from inside the box in the 54th minute.
Stamford Bridge was rocking as Chelsea knew they had the beating of United and their momentum got the better of the inexperienced Smalling, when he brought down Zhirkov inside the United box.
Frank Lampard stepped up and fired the ball into the roof of the net to send Stamford Bridge into dream land.
United had no comeback to Chelsea’s onslaught and Ferguson threw on Giggs and Berbatov for Scholes and Hernandez in an effort to claim a point from the game.
However, Chelsea were not going to give up their lead easy and frustrated United by attacking and keeping the ball away from their opponents.
With Michael Owen injured yet again Ferguson had no other attacking option on the bench and put on Fabio for Evra in hope of a miracle.
The night got even worse for United when Vidic was sent off for a second yellow card when he brought down Ramires in stoppage time.
United must now travel to Liverpool on Sunday without Vidic, and could be in second place by the time they kick off.