Just four minutes into the match at 1.30pm GMT, Lauren James progressed down the left before slipping a pass to Thompson, who fed Johanna Rytting Kaneryd. The Swedish forward couldn't get a shot away, but the home side control the tempo.
Chelsea vs Manchester United: Women's FA Cup Live
The Women's FA Cup fifth round sees Chelsea host Manchester United at Kingsmeadow, with the Blues already dominating early possession.