Windsor Ladies First XI suffered a setback to their title hopes after going 4-0 down to Marlow Ladies 4s.
Their heaviest defeat of the season at the hands of a well drilled Marlow side was a shock as top of the table Windsor started the game full of confidence.
Despite losing talisman captain and top scorer Freya Hayter to injury, Windsor's talented squad could have taken the lead but for Marlow's in-form keeper.
A couple of smart saves rallied the visitors who upped the tempo and took the game to Windsor with their constant pressure and plan to shut down play.
They gave Windsor no time on the ball and the hosts suddenly found themselves on the back foot as Marlow broke in numbers.
A terrific clearance off the Windsor goal-line by Ellen Taylor kept them in the game but Marlow won the ball back and swarmed into the D.
And a close range strike just before half time gave keeper Emma Cross no chance as it slammed into the back of the net.
Unexpectedly behind, Windsor battled to equalise in the second half but found it difficult to contain Marlow and conceded again.
Forwards Maxine Bonnage, Mel Van Huffel and Elle Gatehouse worked tirelessly to get shots away but the Marlow keeper was a match for everything they threw at the goal.
Jessi Nagi and Annalies Hogan helped drive Windsor forward but an organised Marlow defence was impenetrable.
And with Windsor pushing to get a point at least, Marlow capitalised on the widening gaps and scored two more to cap a miserable afternoon for the Trysports Division 1 leaders.
Windsor will now have to sweat it out as they have no game on Saturday, March 7 while challengers Milton Keynes Ladies play Oxford Ladies 4s.
A win would put them level on points with Windsor but still with a game in hand.