It took Luke McGrath’s 74th minute try to finally shake off Glasgow Warriors at the RDS Arena on Sunday evening.

This put the champions in a strong position, holding a six-point lead over Ulster at the top of Guinness PRO14 Conference ‘A’ with three rounds to go.

No sooner had the teams paid their respect to Gary Halpin with a minute’s silence than Leinster had rifled through Glasgow’s defence from carries by Luke McGrath, Josh Murphy and Peter Dooley to apply pressure.

They even turned down an early shot at goal for a lineout which Sean Cronin delivered and Harry Byrne was available for a smart finish and a rudimentary conversion in the third minute.

Ciarán Frawley was withdrawn late to allow for Jamie Osborne’s inclusion from the start at outside centre, Rory O’Loughlin moving to the inside berth.

Prop Dooley and flanker Murphy got through the heart of a Glasgow maul to force a turnover and Leinster’s move from the scrum was designed to put the ball into the hands of Osborne, who crisply fed Cian Kelleher.

From the next scrum, half-backs McGrath and Byrne engineered the space for Dave Kearney to make ground.

Byrne, back on the ball, spun out of a tackle, Dooley put the head down and McGrath was inches short before Byrne’s kick for Kelleher led to a penalty try and Cole Forbes being binned for a tackle in the air in the 10th minute.

The Scots had to get hands on the ball and ask a few questions. When they did so, wing Kelleher was offside and they had their first attacking position inside the 22.

Glasgow went direct when Huw Jones broke the line and flanker Thomas Gordon was there to pick the ball off his bootlaces for a fine try, converted by Adam Hastings to halve the deficit.

Then, centre Jones snagged O’Loughlin in the backfield and Jimmy O’Brien was forced to launch the ball downfield, Dave Kearney’s work earning a Leinster lineout.

A sweet move from a smooth lineout was good for a healthy gain and another penalty to the corner.

Cronin found Josh Murphy rising high at the lineout. O’Loughlin stepped inside the first defender, Byrne swerved through traffic, Dooley picked and drove and Scott Penny, operating at number eight, powered over for the third try, converted by Byrne for 21-7 in the 21st minute.

When back-to-back penalties from the home side and a burst by Jones up the middle came to nothing, Scott Fardy snatched a lineout against the throw.

Glasgow came hard again. Out-half Hastings and Jones threatened the line and Leinster’s discipline slipped.

Rufus McLean almost got around the quick recovering Osborne. McGrath ripped the ball free near his own line and old heads Cronin and Fardy ran the ball out of defence to the 22.

The Blues could not break free. Another lineout brought another attack in which Osborne corralled McLean again and quickly hammered into Leone Nakarawa.

The well-rested Forbes broke two tackles and Ollie Kebble pounded out hard yards for the kind of momentum Glasgow thrive on until Byrne and Penny forced a knock-on from Nakawara.

It was at this point Byrne was withdrawn permanently for a Head Injury Assessment for David Hawkshaw to come in at out-half just ahead of Dooley forcing a spill out of Ryan Wilson.

Then, Hastings was sent off for dangerous play, bringing his boot high enough to catch Kelleher flush in the face, Max O’Reilly coming in as a blood substitute.

The fluidity of the first quarter was succeeded by patchy play from both sides in the lead up to Penny banging to the line from a quick tap penalty when referee Frank Murphy whistled a free-kick at a Leinster scrum, securing the fourth try and Hawkshaw notching the conversion for 28-7 at the interval.

Glasgow could have used the numerical disadvantage as an excuse. Instead, they put together a superb attack, Sam Johnson driving straight, hooker Grant Stewart charging out of a tackle and wing McLean accelerating to the line.

Replacement Ross Thompson, in at out-half, converted from the touchline to make it a double-scores game in the 43rd minute.

Not content with that, Glasgow benefitted from Leinster’s trend for conceding penalties, working on the advantage rule to move with menace, Jones carrying to the whitewash, Thompson’s extras making it 28-21 in the 52nd minute.

The message was clear: Glasgow were not going to go quietly. The Blues were patient in how they worked through 20 phases in the face of defiant defence.

Twenty-year-old Alex Soroka entered for his first cap in the 58th minute as Glasgow turned over a maul and cranked out a scrum penalty.

A tremendous counter-ruck from Josh van der Flier almost created a turnover before Thompson tumbled a kick inside the 22.

It took Fardy’s contest at a lineout, Penny’s alert reaction to the loose ball and a double hit by Penny and van der Flier on captain Wilson to provide the basis for McGrath to kick and van der Flier to grab Jones.

Two strong carries and a key interception from Soroka allied to a strong break from Hawkshaw were undone by Leinster’s lack of fluency.

Certainly, Glasgow could have done without the binning of replacement TJ Ioane, for a shoulder charge into Jimmy O’Brien.

Leinster went to width, O’Brien sending Kearney up the tramline and McGrath taking the final pass to scoot to the left corner, Hawkshaw converting in the 74th minute.

Rubbing salt into an open wound, flashing hands put O’Brien into space. He drew the final defender to put Kelleher over for the sixth try in the 78th minute.