George Baldock says United's recent excellent defensive record has been a real 'team effort'.
The Blades have racked up seven consecutive clean sheets in the league, but Baldock acknowledges United will have to hit the ground running following the international break against Bristol City.
He remarked: "When you start to get those clean sheets, the confidence is rolling and we've got some brilliant defenders and a really good goalkeeper.
"But it is about more than that, the Gaffer and Alan Knill are very hardworking about snuffing out the threats of the opposition and working on team shape.
"The front two work as hard as anyone, it's certainly a team effort and we've just enjoyed a really good run defensively, whilst being good on the ball also."
Of the Robins, Baldock added: "They are a really good team, they are athletic and have some really good players.
"They've got a manager who likes to play the right way and it'll be another difficult test, we saw at their place they can beat anyone on their day."