Coached by John McClean and Vinny Hammond, the UCD Under-20s have already won the Conroy Cup and Maher Cup titles this season and they will be eager to put one over on the All-Ireland champions.
UCD had a number of their underage players on AIB League duty last weekend - ironically against UL Bohs - and with those players available for Saturday's game, 'College are favoured to advance to the final.
There are two obvious factors pointing to a UCD win - the match is being played at Belfield and UL Bohemians also missed out on 80 minutes of rugby last weekend, following their walkover over Ulster opposition at the quarter-final stage.
However, coach Mike Nix is confident that the UL Bohs squad will give a good account for themselves and they are sure to relish the underdogs' tag and the fact that they are the only Munster representatives left.
The other semi-final will see the Under-20s of Blackrock College and Lansdowne go head-to-head at Stradbrook.
A close affair is expected and both teams seem to be in a rich vein of form, judging by 'Rock's 50-10 quarter-final victory at Dungannon and Lansdowne's 32-10 quarter-final defeat of Buccaneers at home.
When the sides met at Ballycorus in November, Lansdowne scored a 20-8 win. Their most recent meeting, at Stradbrook in February, went 'Rock's way (17-16).
Both of those games were in the JP Flanagan Premier Super Six Group 1, which Lansdowne comfortably topped with seven wins out of eight.
Lansdowne boast a particularly strong back row unit and are well able to take their scores, but the same can be said of Blackrock.
Adding to the intrigue, there should be a number of this season's Ireland Under-20 players facing off against each other, including Blackrock place-kicker Ian Madigan and big Lansdowne centre Eamonn Sheridan.
Notably, Blackrock are unbeaten in their last five games - including their 29-12 All-Ireland qualifier victory over St. Mary's College - and they looked poised to make it six at Lansdowne's expense.
FRAZER MCMULLEN TROPHY ALL-IRELAND UNDER-20 CHAMPIONSHIP SEMI-FINALS:
Saturday, April 4 -
UCD v UL Bohemians, Belfield, 2.30pm
Blackrock College v Lansdowne, Stradbrook, 2.30pm