Douglas kept the pressure on their promotion rivals in South Lancashire/Cheshire Division Two with a 23-7 win over struggling Trentham at Port-e-Chee.
Douglas led 8-0 at half-time thanks to a try and a penalty from the in-form Scott Goodall.
In the second half they added to their tally with tries from skipper Ryan Maddox and Stu Ansell.
Goodall added his second penalty and there was also a conversion from Mark Shortland as Douglas tried in vain for their fourth try and that desperately needed bonus point.
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