Fergie made ten changes to the side that drew at Goodison Park at the weekend but the side he fielded found themselves struggling against Rangers’ blanket defence.
And once Antonio Valencia had been stretchered from the field with a badly broken ankle, United lacked anyway of unlocking the stubborn Rangers’ defence.
"We wanted to see how Javier Hernandez would do in a full game," said Ferguson.
"Because of that we left Berbatov out and his form has been absolutely fantastic. He has been one of our best players this season and his ability to create in tight situations would have made a difference."