Brentford's Women exited the Capital Women's Intermediate Cup with a derby defeat on Sunday.
The Bees beat Enfield Town Reserves in their first game in the competition, which they won last year, but could not extend their run.
Queens Park Rangers Reserves scored a goal in each half to take a 2-0 win and secure their spot in the last eight.
Brentford were hit before kick-off with the loss of their regular goalkeeper Caroline Brooks and top scorer Ashley Cheatley.
Tia Prior stepped up to play between the sticks and made a number of good saves before a scruffy shot worked its way in late in the first half.
Lisa Grant had a chance to equalise in the first half and Dana Johnson caused problems in the second but QPR secured the win with a goal on the break.
The Bees return to league action and face Hemel Hempstead Town on Sunday.
More information on fixtures and results can be seen here.