Millwall boss Neil Harris says his team will have to be at their best defensively against Sheffield United.

The Blades are the second-highest scorers in the Championship and travel to the Den on Saturday.

Both clubs won promotion to England’s second tier last season, and Sheffield United have carried their momentum into the new campaign. They are third, just three points off the top two.

Harris, whose Millwall side boast a strong defensive record with seven clean sheets this term, said: “The game is going to be really tough.

“They’ve got themselves into a good position. Leon Clarke, Billy Sharp and Mark Duffy are in unbelievable form.

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“That’s what separates the two teams at the moment – they’ve got players in-form scoring goals and we’ve got players in-form but without the goals.

“Leon Clarke has dragged them into the top three through November.

“They’ve carried on their momentum from last year, so we know we’re going to have to be at our best defensively, which we have been pretty much all season, because they play open, expansive football and they’re enjoyable to watch.

“I’ve been very impressed with Sheffield United. But it’s a chance for us on the back of a really good second-half against Hull to carry that momentum to try to get back to winning ways at the Den.”