Douglas put in a ruthless performance to beat Ramsey 26-6 at Mooragh Park and retain the Manx Cup.
Ramsey led 6-0 early on through two Fintan Cummins penalties but Douglas gradually took control of the first half and tries from Daryn Thompson and Andy Evans, plus a penalty from Bryn Snellgrove, gave them a 13-6 advantage at the break.
Snellgrove struck with another two penalties at the beginning of the second half to stretch the lead to 19-6 before a Carl Markle-Fearns try, converted by Snellgrove, made the game safe.
Vagabonds lost 32-22 away at Marple and missed out on third place in South Lancashire/Cheshire Division Two.
The game was all square 7-7 at half-time.
Vagas took control early in the second half and led 22-7 before a late Marple rally sealed the win and with relegation rivals Oldershaw losing, guaranteed Marple their place in the league next season.
There was some good news for Vagabonds Ladies when the only team capable of overtaking them, Northwich, lost 19-15 away at Preston Grasshoppers.
Vagas have one remaining fixture s at Ballafletcher on May 11 against bottom side Crosby St Marys.
A win will give them the title.