United women fell to a narrow defeat against FA Women's Super League side Aston Villa in the Continental Cup, with only a penalty just before half-time separating the sides.
Head coach Neil Redfearn gave a full debut to Olivia Chane, while Courtney Sweetman-Kirk made her debut from the bench, with Becky Flaherty and Nat Johnson also returning to the squad.
The Blades started well and more than matched last season's FA Women's Championship winners, but couldn't find an end product on a night where half chances came and went.
Former Villa striker Mel Johnson tested Lisa Weiss early on, before the goalkeeper had to be alert to push behind a fierce effort from Veatriki Sarri.
The hosts did grow into the game but their chance to open the scoring came just as United were putting together a sustained spell of pressure.
Ellie Wilson was adjudged to have fouled Jodie Hutton in the box, the Villa winger stepping up herself to score what would be the decider.
Fran Kitching did well to deny Villa a second in first half stoppage time and the Blades came out fighting again after the break.
Maddy Cusack saw an effort from distance saved before Johnson just couldn't get on the end of Katie Wilkinson's cross into the box.
It looked like the Blades had got the equaliser their efforts deserved, but Jade Pennock's strike in the 90th minute was disallowed despite no obvious foul on Weiss from a United player.
Either way, Redfearn was pleased with his side's efforts against FA WSL opposition.
"I thought we played really well. I thought the penalty we got given against us was a bit dubious and then a goal disallowed at the end where I think it's their player who nudges into the keeper before Jade puts it in.
"We can count ourselves unfortunate. We had the share of possession, played some really good stuff and at times were dominant. We defended really well but sometimes it goes that way, 1-0 either way, but we did enough to get a result out of it.
Blades: Kitching, Wilson, Little, Hartley, Lipka (Walton 71), Pennock, Cusack, Wilkinson, Sarri, Chance (Sweetman-Kirk), M. Johnson (Lord-Mears 82).
Unused: Flaherty, N. Johnson, Paul, Dixon, Matthews, Coan.