The Drogs lead 2-0 going into the tie at United park which kicks off at 7.45pm
Wexford Youths await whoever gets through the tie in the Promotion /Relegation play-off.
The Premier Division season draws to a close tonight as Champions Dundalk host Galway Unitey and second-placed Cork City travel to the Carlisle Grounds to face Bray Wanderers.
Elsewhere, Finn Harps are at home to Bohemians, Shamrock Rovers travel to Longford Town, St Pat's host Derry City and Wexford Youths are away to Sligo Rovers.
