Glasgow City moved to within six points of SWPL leaders Rangers after coming from behind to dispatch Montrose.
Tammy-Lee Harkin nodded the hosts into a shock lead, but Kenzie Weir and Carlee Giammona's headers in reply put City ahead.
A stunning Fiona Brown lob made it three, and the Scotland international grabbed her second 15 minutes later at the near post.
Mairead Fulton completed the rout, firing home from outside the box.
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