Hampshire Division 1 side USP were pushed all the way by their two-divisions lower opposition before coming away 4-3 victors in the last-eight tie.
US Portsmouth had Beth Smith (two) along with strikes from Lovedeep Singh and Anee Unsworth for seeing them through.
Fleetlands had earlier stunned USP by going 2-0 to the good but Sarah Butterworth's double and Ellie Hilton's effort were not quite enough to see them through.
1. Sarah Butterworth struck twice for Fleetlands Women
Picture: Neil Marshall Photo: Neil Marshall
2. US Portsmouth goalkeeper Gemma Needham saves from Ellie Hilton
Picture: Neil Marshall Photo: Neil Marshall
3. US Portsmouth's Beth Smith gets a talking to from the referee
Picture: Neil Marshall Photo: Neil Marshall
4. Beth Smith lobs over the goalkeeper and into the net
Picture: Neil Marshall Photo: Neil Marshall
1 / 2