Young Munster and UL Bohemian played out their re-fixed league ties with Dublin University and Ballynahinch with both Limerick sides losing out to late tries on bank holiday Monday.
In College Park a Ger Slattery try followed by a brace by Munster Academy back Alan Tynan had Young Munster 19-11 to the good with two of the three conversions going between the posts.
However, a penalty followed by a last minute from Trinity ensured that the cookies had to settle for a losing bonus point in the capital as the game finished up 21-19.
2 late tries see both Limerick sides lose out in today's #UBL action. Big loss for @YoungMunsterRFC in terms of semi-final hopes.
— Luke Liddy (@LOLIDDY2489) March 19, 2018
Young Munster now sit four points back from Clontarf who occupy the last remaining semi-final place with three games to go.
In Division 1B UL Bohemian were also outdone by a late try as they lost out 24-17 to a Ballynahinch side who now sit top of the table.
Christy Neilan’s men trailed 9-7 at the break with their try coming from Jamie McNamara with Robbie Bourke adding the extras.
Bohs took the lead midway through the second half through a Dara O’Grady try, which was converted, again by Bourke.
The visitors reclaimed the lead through a try after 70 minutes before Bourke struck back with a converted penalty to level up matters at 17 all.
There was late heartbreak for the Limerick side, though, as Ballynahinch crossed the whitewash in injury time to seal the win.