Witney ended a disappointing season on a high note by beating Littlemore 39-14 at Abingdon to qualifying for the Tetley's Bitter Cup for the first time.
A superb first-half display, during which they raced into a 39-0 lead, put Witney in charge of this play-off between the two Oxfordshire Cup losing semi-finalists.
So, Witney now join Henley and Banbury as Oxon's representatives in this national competition next season.
With a dominant performance by New Zealand flanker Dan Hillis, Witney made a storming start.
Winger Nathan Phillips raced over for two tries, and with Francis Grant adding a conversion and a penalty, Witney were 15-0 up in as many minutes.
The scoring spree continued with Witney scoring further tries from outstanding flanker Dean Townsend, an individual effort from winger Ben Dunmore and an opportunist score by skipper Paul Thomas.
Grant's landed three more conversions and a second penalty to put Witney out of reach at the break.
Littlemore forwards raised their game in the second half and denied Witney any sight of the ball.
Pressure brought them a penalty try, while their No 8 went over under the posts.
But Witney's lead was never threatened, and so they ended a season of struggle in South West Division 2 East by making club history.
There could be more good news round the corner for Witney, as they could escape relegation, despite finishing in the bottom two.
If Slough beat Stroud in the play-off between the runners-up in the South West 2 divisions, Witney will stay up.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article