On a difficult surface and in breezy conditions, Jersey came home 3-1 winners after Jason De Andrade gave them the perfect start with a rising half-volley goal in the sixth minute.
De Andrade timed his run to perfection to meet a quality cross into the area from Jordan McBride.
Devon equalised 16 minutes from the end, prodding the ball over the goal-line following a mêlée in the goalmouth after a corner kick.
Substitute Declan Sowney had a goal ruled out for offside in the closing stages leaving the match to go into extra time.
Jack Boyle restored Jersey’s advantage when he cut the ball back across the face of goal and in-off a post on 102 minutes.
Just three minutes remained when Jersey got their third, Sowney getting the final touch on a free kick which the hosts’ defence failed to clear.
Jersey manager Dave Walsh said: ‘It’s a good result, it was a very good team effort.
It was difficult to play a passing game on a bumpy surface so we had to knock it long, hold the ball up and get the midfielders supporting.
‘The players worked tirelessly and deserved their win, the opposition were not as good or as physically strong as the last team we played while our performance was much more encouraging.’ Jersey will now play either Wiltshire or the Army, by 1 February 2007, in the semi-finals of the competition.
The other semi in the South and West Counties Championship KO is Oxfordshire v Berks and Bucks or Hampshire.
Jersey: Max Jouan; Luke Campbell, Ben Cairney (Tom Wiggley, 45), Sam Habin, Pierce Cummins; Callum Black (Declan Sowney, 89); Jason De Andrade, Michael Weir, Darren A’Court, Jordan McBride (Danny Flynn, 78); Jack Boyle.