Onchan surprised Ayre United in the GH Corlett Woods Cup preliminary round.
Craig Marsh, Mark Burman, Gerard Colligon and Mark Rees were on target in a 4-2 home win.
Phil Quayle and Elliot Cureton replied for the Tangerines.
Douglas Athletic are up to fifth in JCK Division Two after an 8-1 thrashing of Braddan.
A Josh Green treble, a Liam Dawson double and further goals from Darren Shields, Andy Newton and Stuart Monks (penalty) secured the three points to lift them above Colby in the table.