While it was a painful defeat for La Rochelle, the victory extended Leinster’s winning sequence to eight in all competitions since their United Rugby Championship loss to Munster at Croke Park in October.
Leo Cullen’s side came into the game beset by front-row injury troubles, with Tadhg Furlong, Andrew Porter, Rabah Slimani and Jack Boyle all missing.
However, they still produced a blistering start as Kenny finished two sweeping moves in the corner with Ireland head coach Andy Farrell watching in the stands.
But the hosts struggled to maintain momentum as Tommy O’Brien was sin-binned for a deliberate knock-on during a promising La Rochelle attack.
Having been made to wait, Niniashvili struck for the Top 14 outfit in the 28th minute, with Leinster’s woes deepened when Joe McCarthy was sin-binned before half-time.
While Leinster – who lost Ireland internationals Ciaran Frawley and Paddy McCarthy to injuries – held La Rochelle scoreless with Joe McCarthy off the field, Le Garrec slotted a penalty over and converted West’s try to give La Rochelle a 17-12 lead.
La Rochelle were guilty of spurning try-scoring opportunities, however, and they were made to pay when Van der Flier and Henshaw both crossed in the right corner in the space of four minutes to move Leinster clear.
However, with Prendergast and Byrne both having missed conversion attempts, La Rochelle edged ahead when Le Garrec coolly added the extras to out-half West’s second score, leaving Leinster on the brink of a first pool defeat since 2018.
Then, in a dramatic denouement to their seventh meeting in the past five years, Leinster earned a late penalty, allowing Byrne to step up and seal a fourth straight win over La Rochelle amid ecstatic full-time scenes in Dublin.
