Douglas lost out 23-11 to Whitehaven to end their RFU Vase hopes.
The visitors to Port-e-Chee are top of their Cumbria league and unbeaten so far this season.
Douglas took an early lead through two Bryn Snellgrove penalties but by half-time, tough tackling Whitehaven were in control 13-6.
A Mike Hebden try in the second half gave Douglas a glimmer of hope but, in the end, Whitehaven were just too strong.
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