Brentford's Women were beaten by one of their fellow promotion chasers last week.
The Bees are in a group of teams chasing league leaders Camden Town but lost to Colne Valley, who are leading the pursuit.
Colne Valley took a half time lead but by the most slender of margins, 1-0.
Brentford tried to get back in to the game but as they chased goals they were hit at the other end.
A Lucy Easton goal was scant consolation for a 6-1 loss.
Colne Valley are second in the London and South East Regional Women's Football League London Division table, six points behind the leaders.
The Bees are fifth, four points further back.
More information on fixtures and results can be seen here.