Three goals in ten minutes and a late Khadija 'Bunny' Shaw strike clinched a famous victory at Leigh Sports Village, as Gareth Taylor's side produced a stunning second half display to turn a thrilling tie on its head after the Reds had opened the scoring early on through Katie Zelem.
The half-time introductions of Derby heroine Caroline Weir and Hayley Raso provided much-needed impetus with Weir on the scoresheet against United for a fourth time, after Lauren Hemp had levelled and Ellen White put the visitors in front.
The victory ensured back-to-back Derby wins but most importantly, clinched our spot in the last eight.
The quarter-final draw is set to take place on Tuesday 1 March from 09:15 (UK), broadcast live on BBC One's Morning Live show.
City’s only previous triumph at Leigh Sports Village had come in the FA Cup with Ellen White bagging a brace in January 2020.
It was the England striker – fresh from helping England to success in the Arnold Clark Cup, who carved the game’s first chance, curling into the arms of Mary Earps within three minutes.
The visitors were let off the hook five minutes later as Maria Thorisdottir somehow headed over the bar from a matter of yards out, after a wayward backpass had gifted United a cheap corner.
Ellie Roebuck then produced an excellent fingertip stop to deny close friend Ella Toone, who unleashed a powerful effort goalward but United would break the deadlock through the resulting corner as Zelem’s delivery evaded everyone and swung into the far post.
City responded well to the setback but struggled to carve any clear-cut chances against a hassling United press. Lucy Bronze came the closest to a first-half leveller with a powerful strike that flew just wide of the post, while Martha Thomas forced Roebuck into a low stop at the other end.
In a bid to inject some pace and creativity, Taylor made a double change at the break, introducing Derby heroine Caroline Weir and Hayley Raso, and the latter almost made an instant impact – only to head straight at Earps, as the away side came flying out of the blocks.
The Australian would not have to wait long to make her mark though, latching onto Georgia Stanway's excellent through-ball and clipping in for White who could not connect but diverted the ball into the path of Hemp at the backpost, who slid the ball across Earps and into the far post.
Four minutes later, City were in front as White capitalised on Hannah Blundell's defensive error, latching onto the short backpass, rounding Earps and slotting home to stun the home crowd and delight the jubilant away following behind the goal.
They were even happier in the minutes that followed when Weir made it three, collecting Hemp's pass, cutting inside and drilling through the United 'keeper and into the near post.
Desperate to claw themselves back into the game, United rallied but struggled to breach the City defence for a second time – Alessia Russo and Toone both firing off-target.
City put the tie well beyond doubt though with a fourth with little more than ten minutes remaining. Once again, it was a case of inspired substitutions as Julie Blakstad drew a low save from Earps, who could only parry into Shaw's path and the Jamaican striker made no mistake, finishing with aplomb to cap a sensational second 45 for City.
Blakstad would have the ball in the back of the net for a fifth time, converting from close range after Raso's effort had been blocked but the goal was ruled out for a foul on Ona Batlle in the build-up.
Four would do just nicely, however!
How we lined up...
Taylor named an unchanged side from the one that edged the league meeting a fortnight ago - the only change seeing youngster Ruby Mace omitted from the bench.
Captain Steph Houghton is set to endure a spell on the sidelines, having undergone surgery on an Achilles injury in the week.
CITY XI | Roebuck, Bronze, Kennedy (Angeldahl 82'), Greenwood, Stokes, Walsh, Losada (Weir 46'), Stanway, Park (Raso 46'), Hemp (Blakstad 76'), White (C) (Shaw 76')
SUBS | Keating, Beckie
UTD XI | Earps, Thorisdottir, Blundell, Toone, Thomas (Hanson 64'), Zelem (C), Galton (F Fuso 82'), Groenen (Boe Risa 82'), Caldwell, Batlle, Russo (Bruun 64')
SUBS | Baggaley, Harris, Smith, Jones
Player of the Match: Lauren Hemp
Once again at the heart of City's best attacking moves, the winger starred and played a key role in our comeback, finishing well for the equaliser and grabbing an assist to set up Weir for her standard Derby goal!
The meeting marked the tenth Manchester Derby between the two sides with City unbeaten in seven of those fixtures, winning five.
City have a 100% record of reaching the FA Cup quarter-finals.
Next up for City is the eagerly-awaited Continental Cup Final against Chelsea.
The showpiece takes place on Saturday 5 March at Wimbledon's Plough Lane with kick-off set for 17:15 UK time.
Tickets for the game - and all City home games - are available.
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