Gymns booked their place in the MBL Floodlit Cup but only after being given a scare by Peel on Sunday.
Goals from Mia Brigantova, Alannah Hall and Eleanor Gawne saw them through after the westerners had led 2-1 at the Bowl.
Their markswomen were Katie Meads and Ellan Cleator.
Corinthians, who had already qualified for the last four, finished as group winners with a 4-0 win over a resolute Rushen, courtesy of goals from Charlotte Wynne-Smythe, Sarah O’Reilly, Shannon Groves and Stephanie Hall.
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