Vidic headed home United's winner seven minutes from time and Ferdinand pulled off a last-ditch block in his penalty area to deny substitute Victor Anichebe an equaliser after Edwin van der Sar had saved James McFadden's effort.
Ferguson was delighted with United's third 1-0 win in succession and with the contribution of his centre-back pairing.
"Vidic is a marvellous centre-back," Ferguson told Sky Sports News.
"Johnson and Yakubu are a real handful and it is not going to be easy for anyone coming here so it's great for us to get the three points.
"Nemanja had the determination and courage to score in their penalty box at a great time for us and Rio showed real determination in his area to get a block in when we needed to see it through."