Leinster withstood a dramatic second-half comeback from Ulster to secure a 29-21 victory in a pulsating Irish derby at the Affidea Stadium in Belfast, climbing above their rivals into third place in the United Rugby Championship standings.
The visitors dominated the first half and led 15-0 through James Culhane and Jimmy O'Brien tries.
Despite making 12 changes from their Champions Cup quarter-final lineup, Leinster controlled the opening period, denying Ulster any attacking rhythm. Early injuries to Ulster's Angus Bell and James Hume compounded the home side's struggles. Culhane powered over after sustained pressure, with Sam Prendergast adding the conversion and a penalty. Just before halftime, Hugo Keenan's clever pass sent O'Brien sprinting into the corner, extending the lead.
Leinster appeared to have sealed the result early in the second half. Robbie Henshaw sliced through under the posts, and Prendergast soon crossed for the bonus-point try, converting both to stretch the advantage to a commanding 29-0.
However, the game transformed dramatically. Ulster launched a stunning fightback, spearheaded by the Ward brothers. Bryn Ward crashed over first, before Zac Ward scored two quickfire tries, all converted by Nathan Doak. The momentum swung further when Leinster's Max Deegan received a 20-minute red card for a high tackle on Werner Kok.
Despite the numerical advantage and surging belief, Ulster couldn't find the two additional scores needed in the closing stages. Leinster's defense held firm under intense pressure to clinch a crucial late-season victory.
The win moves Leinster into third place with three regular-season rounds remaining, while Ulster drop to fourth, leaving both sides firmly in the playoff hunt.