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There's been success for Chelsea already today as goals from Guro Reiten and Ji So-yun sent them through to the Women's FA Cup final with a 2-0 win over rivals Arsenal.

Watch the highlights above.

Phil McNulty
BBC Sport chief football writer at Wembley

There was an element of gamble about Crystal Palace's appointment of Patrick Vieira as manager in the summer but no-one can question the decision now.

Vieira, who won the FA Cup five times as a player, has a more youthful Palace side playing attractive football and has the personality to take these players with him on the big occasions. He has been there and commands total respect.

Palace will really fancy their chances today.

Image source, Getty Images

Crystal Palace are looking to reach the FA Cup final for the first time since 2015-16, when they were beaten 2-1 by Manchester United.

Boss Patrick Vieira won the competition five times as a player - four times with Arsenal and once with Manchester City.

"It's been the fact that I've been in places where clubs are successful in the FA Cup. I was just part of it," said the former France midfielder.

"This is a different club, team and ambition and it is a really good moment for the club.

"The message to the players and fans is to enjoy the day. We had a really good week of preparation and we will be ready."

Image source, Getty Images

Chelsea are appearing in their 26th FA Cup semi-final, with only Arsenal and Manchester United (30 each) appearing in more.

Fifty percent of these appearances have come since the turn of the millennium (13), at least three more times than any other side over that timeframe.

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Conor Gallagher may not be able to play but he's at Wembley to support from the sidelines.

Give us a wave, Conor!

Image source, Getty Images

Thomas Tuchel personally apologised to Conor Gallagher after Chelsea blocked the Crystal Palace midfielder from facing his parent club in today's semi-final.

Palace made an official request to the Blues but it was turned down because of the terms of Gallagher's loan deal.

The 22-year-old has impressed since joining Palace last summer, and made his senior England debut in November, but Tuchel insisted Chelsea's decision was the right one.

"I had the chance to speak to Conor, and I could also see his frustration," he said. We met some weeks ago, we met after the international break by coincidence in a restaurant, and we had a chat and the subject came up. And I apologised."

It's three changes for Chelsea from the team that were agonisingly beaten by Real Madrid last time out.

Thiago Silva, Ruben Loftus-Cheek and N'Golo Kante miss out. Andreas Christensen, Cesar Azpilicueta and Jorginho come in.

Chelsea: Mendy; Azpilicueta, Christensen, Rudiger; James, Jorginho, Kovacic, Alonso, Mount, Havertz, Werner.

Subs: Kepa, Thiago Silva, Sarr, Kante, Loftus-Cheek, Saul, Pulisic, Ziyech, Lukaku.

Crystal Palace make four changes to the side that lost 2-1 to Leicester City last Sunday.

Jack Butland, Joel Ward, McArthur and Eberechi Eze come in.

Out are Vicente Guaita, Jordan Ayew, Nathaniel Clyne and Conor Gallagher. The latter is not able to appear against his parent club.

Crystal Palace: Butland; Ward, Andersen, Guehi, Mitchell, Kouyate, McArthur, Schlupp, Eze, Mateta, Zaha.

Subs: Guaita, Clyne, Kelly, Tomkins, Milivojevic, Ayew, Olise, Benteke, Edouard.

Alex Howell
BBC Sport at Wembley Stadium

Crystal Palace manager said on Friday that Tyrick Mitchell and Michael Olise would 'only be involved in the game if they are 100%.'

Both of the players are in the squad and have done enough to prove to him they're ready. Mitchell from the start and Olise and option from the bench.

Olise hasn't been available for Palace since leaving the French U21 squad in the international break.

Timo Werner starts in attack for Chelsea, who make three changes from the Champions League game at Real Madrid in midweek.

Tyrick Mitchell starts for Crystal Palace while Michael Olise is on the bench. There's no Conor Gallagher because he is unable to play against his parent club.

Full team news to follow.

Chelsea: Mendy; Azpilicueta, Christensen, Rudiger; James, Jorginho, Kovacic, Alonso; Mount; Havertz, Werner

Subs: Kepa, Thiago Silva, Sarr, Kante, Loftus-Cheek,Saul, external, Pulisic, Ziyech, Lukaku

Crystal Palace: Butland; Ward, Andersen, Guehi, Mitchell; Kouyate, McArthur, Schlupp; Eze, Mateta, Zaha

Subs: Guaita, Clyne, Kelly, Tomkins, Milivojevic, Ayew, Olise, Benteke, Edouard

Former Crystal Palace boss Ian Holloway is looking dapper for this game.

He led the Eagles to promotion to the Premier League in 2013 with an extra-time win over Watford at Wembley.

Image source, Getty Images

Thomas Tuchel is hopeful Chelsea can bounce back from their Champions League exit by progressing to the FA Cup final.

The Blues were beaten by Real Madrid on aggregate, despite an impressive second-leg fightback in which they won 3-2 in Madrid after extra time.

That performance came after a 6-0 win against Southampton as Chelsea responded to back-to-back defeats to Brentford and Real Madrid in the first leg in some style.

"It's straight away another knockout match," Tuchel said. "We bounced back from the two results and performances against Brentford and Real Madrid at home.

"We won both games after that and there's a big knockout game at Wembley. In my opinion it's a good thing, a huge reward coming with it."

Image source, Getty Images

Chelsea could face one of Europe's most exciting young attackers today - and they will hope they aren't made to regret not snapping him up when they could.

Michael Olise, who is expected to recover from injury to start for Crystal Palace, was a member of Chelsea's youth system before leaving aged 14.

The now 20-year-old is impressing on the Premier League stage, after a rather understated £8m move from Reading in the summer, with two goals and five assists in 22 appearances for the Eagles.

Read more in Harry De Cosemo's feature on Olise here.