They trailed 2-0 at half-time and had Andrew Hughes sent-off after giving away the penalty for the Blades' second goal.
But a stirring second-half performance saw PNE reduce the deficit through Alan Browne's 71st minute goal after good work from Daniel Johnson.
Then in the 89th minute, Emil Riis slid home Ched Evans' cross for the equaliser.
Here on the player ratings on a night of high drama under the Deepdale floodlights, with Browne, Evans and Riis taking star billing.
Then in the 89th minute, Emil Riis slid home Ched Evans' cross for the equaliser.
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