Manchester United have had to wait five years for a first win over Chelsea, but when it came it came in style, two goals in the opening 25 minutes enough to earn them a 2-1 win and a place in a second successive FA Cup final at Wembley at the expense of the holders.

It will be the first time a team that isn’t Arsenal, Chelsea or Manchester City lifts the trophy since 2005, when Charlton beat Everton 1-0 at the Boleyn Ground, after Tottenham booked their place in the final deep into extra time against Leicester.

Related: Martha Thomas breaks Leicester hearts to send Spurs into Women’s FA Cup final

The teamsheet drew the ire of United fans around the ground an hour before kick-off, the inclusion in the starting XI of Rachel Williams, a 36-year-old usually utilised from the bench, prompting confusion.

The “Skinner out” chant has followed the United manager this ­season and before kick-off there was more of the same, their WSL challenge and Champions League hopes over early on and blame laid at the feet of the manager by the fans.

Except Marc Skinner would have the last laugh at Leigh Sports Village, Williams rewarding the manager for his vote of confidence in starting her with an all-action performance that caused the Chelsea backline all kinds of trouble.

“It doesn’t matter,” Skinner said of the criticism that has followed him. “Whether you like me or hate me, I’m still going to be the same person; I’m still going to help, I’m still here to make the team the very best, and if I can deliver that for you in the moment and you still hate me? It doesn’t matter.”

It took less than a minute for United to take the lead, Ève ­Périsset’s hesitant back pass to Hannah Hampton was way too short, allowing Leah Galton to capitalise and skirt forward before swinging a cross to the back post where Lucía García was on hand to turn in.

There is no love lost between these two teams, playing a rematch of last season’s final, which Chelsea won 1-0. “We needed to do something different,” said Skinner, of finally getting the better of Chelsea. “Today, it was about being more direct, sacrificing without the ball.”

United’s second came in the 23rd minute. Ella Toone shrugged off the challenge of Melanie Leupolz on the left, leaving the Germany midfielder on the floor, before she lofted the ball into the middle for Williams to head in and convert the unconverted among the 6,876 crowd. “If you were Chelsea and you were predicting our starting lineup you wouldn’t predict Rachel, so we knew that was an advantage,” said Skinner.

The ease with which Toone evaded Leupolz was symptomatic of the midfield battle, with Chelsea struggling to handle the energy of Toone, Lisa Naalsund and Zelem, and the Blues’ defence increasingly exposed.

This is Emma Hayes’s Chelsea though, and while they have not looked themselves of late, you can never write them off. They had been here before against United, coming from behind twice to earn a 4-2 win that won them the title on the last day of the season in May 2022. In United’s five seasons in the WSL they have failed to earn more than a single point from Chelsea.

The goal that got them back into the game came at a critical juncture, deep into added time at the end of the first half. Niamh Charles’s ball in from the left was fired into the roof of the net by Lauren James, who grappled with Millie Turner as she tried to keep the ball away from Chelsea attempts to race the ball back to the centre of the pitch.

Mary Earps would keep United ahead in the second half, pulling off a fantastic reflex save to keep out James’s effort, as the visiting team increased the pressure in search of an equaliser. Chelsea were unlucky too, twice being denied strong penalty shouts, the first for a Zelem handball and the second for a Williams challenge on Charles.

“Of course [they were penalties],” said Hayes of the two incidents. “I just don’t understand how you can’t give those penalties. I’ve said it a thousand times, to help our officials we need technology in the game.”

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Hayes threw the attacking kitchen sink on with 20 minutes remaining, Catarina Macario and Sjoeke Nüsken coming on as substitutes and then Fran Kirby and Aggie Beever-Jones following them.

It wasn’t enough. At the end of eight added minutes United’s players screamed in delight as the bench and staff spilled on to the pitch. Chelsea players collapsed, the end of Hayes’s Chelsea dynasty crumbling further with their second cup exit, but still the league and Champions League left to play for.