"It is ironic that we are playing them again after the Worthington Cup tie," the Leeds boss told Sky Sports News.
"We thought we played very well against them at Bramall Lane, apart from the closing minutes. They have had two great cup runs this season. They really impressed in getting to the semi-final of the Worthington Cup.
"We face a tough task but we have managed to deal with tough challenges at Scunthorpe, Gillingham and Crystal Palace so far. We will have plenty of respect for Sheffield United. They have shown everyone what they are capable of doing so there can be no surprise factor.
"I was not willing us to stay away from Arsenal or Chelsea. I am always philosophical. Whatever it is it is a great draw and you have to deal with it. We will look forward to going back to Bramall Lane."