It was an industrial performance by United, though having to come from behind after Sean St Ledger's suspiciously offside first half goal. However the first 45 minutes of the game was a particularly poor standard of football from the visitors in comparison to the second which balled North End over.
The Blades began brightly and within four minutes of the start the visitors had carved out an opportunity to take the lead; Darius Henderson found fellow strike partner Jamie Ward wanting, the tricky forward spun inside the box but his low drive was parried away by keeper Andrew Lonergan.
On 21st minute the home side scored what looked a very suspect first goal; a free-kick in the Blades half was lofted into the box, it was headed on by Nick Montgomery and despite being in an off side position Sean St Ledger chested the ball down and with the coolest of finishes slipped past Paddy Kenny.
Moments later it looked as though the Blades had drawn level when Stephen Quinn was put through by Howard but his eight yard shot was shopped by the impressive Lonergan and out for a corner.
North End looked to have doubled their lead ten minutes before half time when Ross Wallace swung in a right sided corner - it was met by Barnsley-born striker Jonathan Parkin who's header crashed against the post for his only opportunity in front of goal.
After a pretty unacceptable first half performance by United its probable that a few unkindly words were dished out to them at half-time; whatever was said worked as 21 seconds into the re-start United levelled.
Andrew Lonergan was in the thick of things again, saving from Darius Henderson's close shot but the ball fell to Jamie Ward who crossed from the right hand side for Brian Howard to volley home his third United goal into an empty net.
After that the home crowed were silenced and maybe the visitors should have gone on to win the game by a confident score line but several substitute players missed opportunities to do so - however they were forced to replace both Darius Henderson and Jamie Ward whom were forced to leave the field through injury.
Their replacements, Craig Beattie and Arturo Lupoli torn the defence apart - but Beattie undoubtedly stole the headlines for his omissible effort close to the final whistle, he was put through on goal and although on the angle was one on one with the keeper, he shot and the legs of Lonergan saved them from losing the tie.
Prior to that after a scrabble in the box he heroically saved Howard's spontaneous volley which was heading goal wards into the right hand corner but was kept out by the plucky shot stopper.
It was clear from his display that keeper Andrew Lonergan was Man of the Match in this game despite the stadium announcer honouring Sean St Ledger via the match sponsors - had it not been for the former England U-21 keeper the Blades could have wheeled out a 3-1 victory to Bramall Lane.
In particular Preston North End had very few opportunities in front of goal in the second half and no doubt will come to Bramall Lane short of confidence. However we must gave praise to Brian Howard who pulled out a spectacular performance despite his critics in recent weeks.