Blades hold Preston
Preston and Sheffield United's respective long unbeaten runs continued after the two played out an entertaining 0-0 draw.
North End, now without defeat in 12 Sky Bet League One games, came close through Joe Garner, Josh Brownhill and Paul Gallagher yet failed to find a way past a Blades defence which kept an eighth straight clean sheet in extending their unbeaten streak to 11 in all competitions.
Despite not conceding in 692 minutes prior to their arrival at Deepdale, the Blades were always likely to get a stern test from the hosts - and so it proved.
Garner nearly profited from goalkeeper Mark Howard's fumble inside 20 seconds and North End's top scorer then glanced a glorious chance wide from Chris Humphrey's inviting delivery.
Conor Coady had the ball in the net at the other end, yet the offside flag chalked that strike off, and it was the Lilywhites who continued to probe with a flurry of chances.
First, Garner's effort was blocked and when Bailey Wright's vicious strike came back in, Blades captain Michael Doyle used his arm to repel the shot. The penalty appeals were unsuccessful and Gallagher drilled another effort in which Howard beat away with his fists.
Nigel Clough's side were struggling to settle - not helped by the fact substitute Matt Hill was taken off at half-time, just four minutes after arriving - and North End kept knocking on the door as Brownhill's shot into the turf bounced up on to the post while Garner narrowly missed the target twice more.
Still Simon Grayson's men came - Gallagher's goal ruled out when Garner was offside and the Leicester loanee then heading straight at Howard - but United, who had won 10 on the spin before this, held firm.