The two Women's Super League sides are looking to reach the Women's FA Cup final for the very first time.
Match preview
Man United will head into the semi-final tie in a confident mood after thrashing Brighton 4-0 when the two sides met in the WSL before the international break.
A Leah Galton brace, as well as strikes from Rachel Williams and Lucia Garcia secured the Red Devils a comfortable victory, which left them top of the WSL table with a one-point lead over second-placed Chelsea, who have a game in hand.
Marc Skinner's side are dreaming of winning the double, but to keep those hopes alive they must beat a WSL side for the first time in the FA Cup this season, after progressing to the semi-finals with three victories over Championship opposition.
Man United will be pleased to have home advantage for Saturday's contest with nine of their 11 competitive home games this term yielding victories.
The Red Devils have also won each of their last four meetings with the Seagulls, including two 4-0 victories in the league this season, and they will believe that they have the quality required to advance to the FA Cup final where they would face Chelsea or Aston Villa.
Brighton, meanwhile, have had an eventful international break after Melissa Phillips was appointed manager, and interim boss Amy Merrick subsequently left the club to become the head coach of the England women's Under-19 side.
Phillips left her position as the manager of London City Lionesses in January to become an assistant coach at Angel City in the National Women's Soccer League in the USA, but she has returned to England, signing a two-and-half-year deal as Brighton boss.
With the Seagulls currently two points adrift from WSL safety, Phillips's main task is to keep Brighton in the top flight, but she has the unique opportunity of guiding the Seagulls into the FA Cup final in her first game in charge.
The South Coast Side began their FA Cup run with a 7-0 victory over third-tier West Bromwich Albion, before going on to beat Championship sides Coventry United and Birmingham City.
Having won just one of their seven away games against WSL opposition this season, Brighton know that they have their work cut out to beat Man United on Saturday.
Manchester United Women Women's FA Cup form:
Manchester United Women form (all competitions):
Brighton & Hove Albion Women Women's FA Cup form:
Brighton & Hove Albion Women form (all competitions):
Team News
Man United will be without the services of Maria Thorisdottir and Lisa Naalsund due to injury issues.
Adriana Leon will not be available after the Canada international completed a short-term loan move to NWSL side Portland Thorns.
Having come off the bench to score three goals in her last two appearances, Garcia could be rewarded with a place in the starting lineup.
As for the visitors, Dejana Stefanovic is expected to be ruled out through injury, while Guro Bergsvand is a doubt after missing the defeat to Man United before the international break.
In her first game as Brighton boss, Williams could decide to utilise a back three made up of Zoe Morse, Megan Connolly and Emma Kullberg.
Having scored eight goals in her 18 competitive appearances this season, Danielle Carter could be presented with a starting opportunity.
Manchester United Women possible starting lineup:
Earps; Batlle, Le Tissier, Turner, Blundell; Ladd, Zelem; Garcia, Toone, Galton; Russo
Brighton & Hove Albion Women possible starting lineup:
L. Williams; Morse, Connolly, Kullberg; Robinson, Olme, Bance, Sarri, Pattinson; Lee, Carter
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