Tevez scored four goals for United as they reach the Carling Cup semi-finals.
“Carlos Tevez had a marvellous performance. It makes my job more difficult but it makes the club stronger,” he told MUTV.
“Both he and Anderson were marvellous.
“I am pretty pleased with the performance. Some of our football was good. There was great invention in our play. The goal with Anderson and Tevez was sensational.
Ferguson continued: “We created a lot of chances and I am satisfied at scoring five goals at home.
“You don’t want to be losing goals and we lost three and that was not a fair reflection on Ben Foster because he had two great saves early in the match which kept us in the game to be honest.
“We just got a bit careless.”