A third-minute try by Cormac Foley paved the way for Leinster to keep their unbeaten record intact in the BKT United Rugby Championship at The Sportsground on Friday.

On a rain-sacked night, the discipline in defence proved to be the difference ahead of Ciaran Frawley’s late penalty to seal the deal.

Initially, Leinster half-backs Cormac Foley and Ross Byrne were given a strong platform by a stream of runners.

Their first lineout led to their opening try, Josh van der Flier bouncing Colm Reilly and feeding Foley for Byrne to convert in the fifth minute.

A big hit by Garry Ringrose on Jack Carty set the tone in defence and Jimmy O’Brien’s catch and careering run threatened to add to Connacht’s problems.

James Ryan’s work on the floor put Leinster back in primary position to strike only for the Men from the West to stand strong through relieving kicks by their half-backs Carty and Reilly.

The footwork of Dan Sheehan and Ringrose was countered by Niall Murray’s pair of lineout steals and two block downs at the ruck to give Connacht momentum.

The Blues stayed patient in defence, coming up collectively to force a spill which was quickly turned into an attack where Josh Murphy was in high on Ed Byrne.

The Connacht maul defence kept Sheehan up off the floor. John Porch’s long kick and Peter Dooley’s strength over the ball enabled Connacht to apply pressure.

The fall of rain meant the ball became elusive, leading to a rise in those lost forward, Liam Turner almost getting around Mack Hansen amid kicks being sprayed all over the pitch.

A power surge from Leinster’s scrum yielded a penalty which Byrne pulled left of the posts as chances were at a premium.

When Connacht earned a shot at reducing the gap from a scrum penalty, Carty preferred to hunt the corner and two subsequent mauls, the second of which Leinster guided into touch to leave it 7-0 at the break.

A chance to regroup would have confirmed the impression that Leinster had to use the wind to their benefit, Charlie Ngatai almost releasing Robert Russell down the left.

Caelen Doris and Ngatai took the ball up. But, Paul Boyle was there to snatch a penalty at the breakdown just as Andrew Porter and Robbie Henshaw came on as reinforcements.

Connacht were able to crack the 22 where their maul was ruined by Leinster’s collective effort to hold them up.

The influence of Henshaw, Doris and Ringrose on the ball was growing as Byrne continued to look for Russell with that arrow-like crossfield kick.

Byrne was uncharacteristically off-target with another penalty before the home troops increased the pace of the game.

Too many times, the green shirts were turned back, Porter the latest to dive on a loose ball and the home lineout malfunctioning to see the status quo maintained.

As ever the set-piece was proving pivotal, Porter crunching a penalty at the scrum and a lineout indiscretion providing another chance for Leinster to turn the screw.

Van der Flier was there to rescue a loose ball and Hansen’s kick out on the full gave up vital metres.

Sheehan’s ball skills and Joe McCarthy’s strong carry were undone by Conor Oliver’s technique over the ball.

A tremendous break by Sheehan up the right enabled Leinster to get in behind where the ball was shifted left for Russell to test John Porch on the touchline.

Then, van der Flier broke away for 50 metres, looking to provide the decisive moment until Porch’s pace saved the night.

However, a yellow card to Niall Murray for cynical play allowed Ciaran Frawley to make it a two-score game in the 77th minute.

Immediately, Liam Turner burst out of the 22 and Jimmy O’Brien’s chase ensured Connacht had to go from deep, something they couldn’t do.