The Blades looked to be cruising when Billy Sharp’s penalty made it 2-0 in the first half, with Andrew Hughes dismissed for fouling Rhian Brewster.
But North End rallied in the second half and goals from skipper Alan Browne and Emil Riis – who scored a late equaliser at Bramall Lane in the first game between these sides earlier in the season – saw the spoils shared.
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United boss Paul Heckingbottom was left fuming at his side’s game management, but his opposite number was left to praise his side’s “fantastic reaction”.
"To have ten men, I just asked the lads to give it everything they've got," said Lowe. "We changed a few things, one or two bodies at half time and when we got the goal back, we felt we'd get another couple of chances.
"I am quite a positive person and at one point I am thinking 'Sheffield United, good team, good footballers, they bounce the ball around and interchange'. At half-time, I didn't want to tell them that and say 'damage limitation', I just said 'right, let's see what we've got and give it your all, give it your fight, give it everything you've got and we'll get an opportunity'.
"Three or four nil, that's damage limitation, but any score line at two-nil - whether it's against ten or 11 men - it is a tough score line, you think 'job done' and maybe they thought that. If they did it backfired didn't it?
"Because we wanted to make sure we were on the front to try and score goals."
Preston's point was well-earned, with United goalkeeper Wes Foderingham making a number of impressive stops from Scott Sinclai and Riis in particular.
But he could do nothing about either goal, with the winner coming from a superb cross from North End substitute and former Blade Ched Evans for Riis to tap home and send the home fans wild.