A Christmas tale of two halves.
For a long time this BKT URC derby threatened to be a real turkey, but it ended up a cracker.
Leinster were 14-0 up at the break thanks to tries from young guns Andrew Osborne and Charlie Tector, while Connacht failed to trouble the league leaders, who have won all ten games this season.
The hosts grabbed the opening score of the second half but Connacht hit back with two tries through Oisin Dowling and Shane Jennings as a first away win against Leinster since 2021 looked on the cards.
But Leinster regained their composure to ensure their winning record remained intact. Leo Cullen's side again made a series of errors and the lineout was a mess at times but they will celebrate Christmas well clear of second-place Glasgow at the top of the table.
Pete Wilkins' Connacht, who face Ulster next Saturday, were worth at least a bonus point but Ross Byrne's late penalty denied them that consolation present. Next up for Leinster is a trip to Thomond Park where Munster await.
After a bright early exchange, with Connacht working their way to the Leinster 22, the game almost came to a standstill with set-pieces, free-kicks and penalties and the accompanying waiting times all that was on view for the 33,963 in attendance on a cold night in Dublin.
Even when the hosts won possession from the lineout, a huge issue last weekend against Clermont, and scrum, they too often coughed up the ball at the next phase.
When Bundee Aki turned RG Snyman over in front of the posts, Connacht partially cleared their lines and some rugby broke out.
Jordie Barrett, named man of the match, combined with Tector to make 30 yards before Josh Ioane was penalised for a high tackle on Gus McCarthy.
But the lineout penalty came to nothing and Snyman again lost the ball just shy of the line.
The hard-running Paul Boyle was doing his best to get Connacht up the field but when his midfield offload didn't find a team-mate, Leinster struck for the opening score in the 20th minute.
Andrew Osborne opens the scoring at the Aviva as Leinster take the lead over Connacht.
— RTÉ Sport (@RTEsport) December 21, 2024
📺 Watch: https://t.co/oyUHkHGBQg
📱 Follow: https://t.co/AHKqPlUwlY #LEIvCON pic.twitter.com/3Wud7jsCmD
They secured lineout ball at the front, with Byrne finding Osborne on a diagonal line, and the left wing evaded a couple of Connacht tackles before diving in at the posts.
Byrne added the extras but Leinster lost captain Jack Conan to injury.
It remained scrappy and Jennings saw yellow for taking Luke McGrath out off the ball after Mack Hansen was turned over after getting attacking ball for the first time.
Leinster bag a second try against Connacht, with Charlie Tector exposing the visitors' defensive frailties.
— RTÉ Sport (@RTEsport) December 21, 2024
📺 Watch: https://t.co/oyUHkHGBQg
📱 Follow: https://t.co/AHKqPlUwlY #LEIvCON pic.twitter.com/NUGDCtQyg3
But, after being so wasteful with early possession and territory, Leinster were clinical off another close-range lineout. The forwards held it in the maul for a few yards before Barrett popped to Tector, who slipped between two weak tackles to score his third Leinster try.
Boyle, Ioane, and Denis Buckley combined to get Connacht within 10 metres but when the out-half spilled it forward, Max Deegan spotted space in the backfield and executed a superb 50:22. Leinster lost the lineout.
Ioane and Deegan both went off for head injury assessments while Leinster continued to make a mess of their lineouts, albeit under good pressure by the visiting jumpers.
Luckily enough, their defence was on top and even when Hansen beat a couple of players, Connacht ran out of support as the phases grew with Alex Soroka coming up with a jackal penalty.
An ironic cheer greeted a successful lineout but Rabah Slimani was adjudged to have gone off his feet at a subsequent ruck and that left Leinster in front 14-0 at the break.
Finlay Bealham was stripped of the ball as Connacht tried to run from deep at the start of the second period and Byrne pushed the lead out to more than two scores after Boyle went offside in defence.
Connacht attacked gamely thereafter but couldn't maintain possession in the Leinster 22 and the only action of note was a harmless pushing match between Snyman and Josh Murphy.
However, Leinster's defence was thinning out and Lee Barron, who had just come on for McCarthy, was in the bin when the Westerners struck in the 53rd minute.
Replacement Oisín Dowling makes an immediate impact on his introduction to score Connacht's first try of the evening against Leinster.
— RTÉ Sport (@RTEsport) December 21, 2024
📺 Watch: https://t.co/oyUHkHGBQg
📱 Follow: https://t.co/AHKqPlUwlY #LEIvCON pic.twitter.com/MDfVFLiIWp
A series of pick and goes after a tap penalty saw replacement lock Dowling touch down but Cathal Forde was off target with the conversion attempt.
Leinster were well and truly on the back foot with Shamus Hurley-Langton carrying with purpose, while Santi Cordero almost reached Hansen's kick first but Byrne was alert to the danger.
Shane Jennings puts the finishing touches to a superb Connacht team try.
— RTÉ Sport (@RTEsport) December 21, 2024
📺 Watch: https://t.co/oyUHkHGBQg
📱 Follow: https://t.co/AHKqPlUwlY #LEIvCON pic.twitter.com/79NTOhCHNv
It was a temporary reprieve. Aki made a break on the short side and Connacht recycled quickly with Darragh Murray and Cian Prendergast shifting the ball to Jennings, who ran in under the posts. Forde's kick made it a five-point game with 18 minutes to play.
Down the other end, Jamison Gibson-Park, who had replaced McGrath, was stopped just short of the line before Osborne was penalised for a neck roll.
The Ireland scrum-half threatened again moments later but stepped into touch to let Connacht get out of their 22.
However, the momentum had swung back Leinster's way and Barron was only denied by an incredible tackle by Prendergast after the hooker had crossed the line.
The pendulum swung back. Hansen tricked his way around a few defenders and Leinster had to scramble and Jimmy O'Brien was sent to the bin with five minutes to go after clashing with the Ireland wing in the air.
Jennings held onto a ball when Connacht attacked down the wing and Darragh Murray fumbled on the 22.
That allowed Leinster to work their way up the field where they earned the penalty that Byrne fired over to seal a nervy win. Connacht will feel they let this one go.
SCORERS
Leinster: Tries - Osborne, Tector
Cons: Byrne (2)
Pens: Byrne
Connacht: Tries - Dowling, Jennings
Cons: Forde
Leinster: Jimmy O'Brien; Aitzol Arenzana-King, Charlie Tector, Jordie Barrett, Andrew Osborne; Ross Byrne, Luke McGrath; Jack Boyle, Gus McCarthy, Rabah Slimani; Diarmuid Mangan, RG Snyman; Alex Soroka, Scott Penny, Jack Conan (capt).
Replacements: Lee Barron (for McCarthy 51), Michael Milne (Boyle 51), Cian Healy (Slimani 51), Brian Deeny (Mangan 75), Ryan Baird (Deegan 33), Jamison Gibson-Park (McGrath 51), Harry Byrne (Arenzana-King 62), Max Deegan (Conan 22).
Connacht: Piers O’Conor; Mack Hansen, Cathal Forde, Bundee Aki, Shane Jennings; Josh Ioane, Ben Murphy; Denis Buckley, Dave Heffernan, Finlay Bealham; Josh Murphy, Darragh Murray; Cian Prendergast (capt), Shamus Hurley-Langton, Paul Boyle.
Replacements: Dylan Tierney-Martin (for Heffernan 58), Jordan Duggan (Buckley 64), Jack Aungier (Bealham 52), Oisín Dowling (J Murphy 52), Sean Jansen (Boyle 52), Caolin Blade (B Murphy 52) , Santiago Cordero (Ioane 32), Conor Oliver (Hurley-Langton 64).
Referee: Chris Busby (IRFU)