Having finished top of the league, Leinster had the advantage of a home semi-final against Ulster in Ashbourne RFC and dominated, winning 48-3.
Tomorrow's game is likely to be close.
Meanwhile, the management and squad wish forwards coach Martin Fenlon a speedy recovery.
Pictured above is Leinster's David McDermot.
Leinster U18: D McDermot, A McGivney, S Moran, J Nolan (C), R Vallejo (New Ross), C O'Brien (Mullingar), J Carbery (Athy), H Hester (Navan), J McKenna (Wicklow), N Hannon (Mullingar), A Purcell (Mullingar), C Joyce-Ahearne (Wexford Wanderers), L Walsh (Wicklow), C Oliver (Skerries), G Dunne (Kilkenny). Replacements: S Healy (Navan), J Barry (Newbridge), J White (Gorey), N Reilly (Ardee), A Feeney (Suttonians), G Lynch (Birr), K Dunne (Tullamore), M Russell (Naas).