Wayne Rooney, Dimitar Berbatov and Nemanja Vidic scored the goals for United.
“It was a great night for us,” Ferguson told Sky Sports.
“They (Chelsea) had a lot of good possession at times and they’re a threat when they get possession.
“They’ve got so many clever players, but we defended well at the 18-yard line so I don’t think they really had a clear-cut chance.
“On the other side our attacking was good and we had some good chances even in the first half, it was a good result.
“We have all the main teams at home and we need to win those games, we have Wigan on Wednesday which will be a tough game.
“We have eight games in January so it’s a big test for us.”
