Berbatov scored both in a 2-0 victory far more comprehensive than the scoreline suggests, with even Black Cats boss Steve Bruce admitting his side deserved nothing from a one-sided contest.
It took the Bulgarian to 13 league goals for a campaign when Wayne Rooney has not managed one from open play. But Ferguson is demanding more from the £30.75million man.
On the way: Striker Berbatov has 13 Premier League goals for the campaign
'There are certain games when we like to play one up front and three central midfield players, Dimitar understands that,' said Ferguson of Berbatov's omission from the starting line-up against Arsenal a fortnight ago, even though he scored five on his previous outing.
'But his form has been terrific. He is on 13 goals now. If he can get us to 25, we need one more to get around that figure, then we will have a good chance.'
Certainly Berbatov will not be allowed to rest on his laurels by Patrice Evra, who revealed he is always on the 29-year-old's back, demanding more.
'I keep moaning at him when he doesn't score in training,' said the Frenchman. 'But he always says "don't worry, I will score in the game". He showed me that.
'He is working hard. He is a good guy and is different class.'
Demands: Ferguson wants goals galore
Without seven key players due to injury, sickness, suspension and ineligibility in the case of Danny Welbeck, Sunderland never stood a chance of repeating their sensational three-goal triumph over Chelsea last month.
'I have heard it said that United are not playing that well,' Bruce said. 'Well, they are unbeaten for six months, so that is not a bad statistic is it?
'They are top of the league, with games in hand, and history suggests they always get better in the second half of the season.'
Next up for the leaders is a trip to Birmingham on Tuesday evening, and unhappy memories for Evra that are unlikely to be erased given the recent chilly conditions.
'Last year, Birmingham was the coldest I have felt in a football match in my life,' he said.
'I have played in Moscow but I have never felt that cold. In the warm up before the game it was difficult to breathe.
'The pitch was hard and overall, it was a nightmare. We have to get ready for the game because it will be very tough.'
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