The Red Devils thumped Reading 4-0 on the opening weekend, while West Ham edged out Everton to claim a narrow 1-0 victory.
Match preview
West Ham have begun the new campaign under new management after Paul Konchesky was promoted from his role as assistant manager following the departure of Olli Harder at the end of last season.
Konchesky has taken over a side that finished in a respectable sixth place last term, and another top half finish this term would certainly be regarded as a success.
However, after ending last season with just two wins in nine league games, West Ham's first priority is to guarantee safety.
Their bid to avoid a relegation battle got off to a perfect start last weekend as Lisa Evans scored what proved to be the winning goal in a home meeting with Everton.
Another home game awaits on Sunday, but the level of the opponent will increase, with the Hammers set to play host to a Man United side that they have lost against in their previous three meetings.
While West Ham opened the new season with a narrow win, the Red Devils blew away Reading to begin the new campaign with a statement victory.
After joining from Brighton & Hove Albion in the summer, Maya Le Tissier marked her debut with a brace, while Katie Zelem and Alessia Russo found the net to wrap up all three points within 35 minutes of kick-off.
Marc Skinner will hope the 4-0 win is just a sign of things to come as his Man United side target Champions League qualification this term.
A title charge will also be a dream, but first and foremost, the Red Devils will look to improve on their travels after finishing last season with one win in their final six away league games.
Although, United will take confidence from the fact that they have only lost one of their previous nine matches in the WSL.
West Ham United Women Women's Super League form:
W
Manchester United Women Women's Super League form:
W
Team News
After beating Everton last weekend, Konchesky may be tempted to name an unchanged lineup for the home meeting with Man United.
Risa Shimizu and Kirsty Smith made their debuts for the Hammers against the Toffees, and the pair will continue to operate in a back four alongside Lucy Parker and Hawa Cissoko.
Debuts were also handed out to Viviane Asseyi and Honoka Hayashi, who will line up in a front three alongside Evans on Sunday.
As for the visitors, Rachel Williams and Aoife Mannion will miss out due to injury issues, while Skinner has revealed Grace Clinton is a doubt.
After scoring a brace in her United debut last weekend, Le Tissier will retain her place in the backline with the Red Devils set to name an unchanged lineup.
Russo will also found the net against Reading, and the England international will be looking to score in consecutive games when she leads the line on Sunday,
West Ham United Women possible starting lineup:
Arnold; Shimizu, Parker, Cissoko, Smith; Ziu, Longhurst, Brynjarsdottir; Asseyi, Evans, Hayashi
Manchester United Women possible starting lineup:
Earps; Batlle, Le Tissier, Turner, Blundell; Ladd, Zelem; Galton, Toone, Garcia; Russo