Athletic took the bragging rights two games to one after drawing each other in three cups in consecutive weeks.
A Calum Best brace and one each for Mark Messenger, Tom Pardini, Greg Quayle, Stuart Gray and Matthew Perry gave Workington the win, while Lewis Little and a brace for Nico Watt replied for Silloth.
In the Hunday Manor Divisional Cup, Borough travelled to Windscale and brushed them aside 7-0.
Dale Hooper hat-trick did most of the damage and there was also a goal each for Lee Woolfe, Robbie Watson, Niall Melton and Shaun Carter.
Gosforth also progressed with a 4-0 home win over Whitehaven Amateurs.
A Jack Denwood brace and one each from Rhys Singleton and Aaron Bradley secured their Semi-Final place.
All remaining games didn’t survive the Cumbrian weather.
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