It was a hard-fought win, with the visitors having to come from behind to secure victory against a Scottish side that, on the whole, edged the forward battle but could not match their visitors when it came to line-breaking flair and the ability to secure tries when they had the pressure.
In the end, it came down to two home mistakes, the first a failure to cover a cross kick, the second losing the ball in their own 22, to give Leinster the scores they needed. In both cases there was still work to do to exploit the opportunities but when they did get these chances, the European champions were ruthless in taking them. That was enough to make all the difference.
Leinster gave an early indication of their intentions when, straight from the kick off, Jonathan Sexton ran from his own line, finding a gap and taking play into to the opposition 22. There were also ominous signs as the Scots pinched the lineout and when they moved play back upfield and won a penalty in the first scrum, kicked by Duncan Weir, the home fly half.
It was enough to give Glasgow some real impetus and, for the next half hour, it was all defence for the Dublin side as the Scots probed for the breakthrough but could not find a chink in the Leinster armour. The visitors could also find confidence from the fact that, though they were under the cosh in terms of territory and possession, they were finding gaps when they had the ball.
Eventually, it worked for them as neat interplay in midfield drove them into the Glasgow half only for Sexton to miss the first penalty when the Scots held on after a tackle but soon made amends by levelling the scores with his second.
The lead did not last long, Weir soon added his second penalty. That only sparked Leinster to life as Fergus McFadden wove his way through the defence to set up wave after wave of attack on the Glasgow line, with Sean O’Brien finishing inches short. The chance went when the Scottish side pinched possession in the scrum under their own posts.
Eventually, the pressure told, though the penalty that allowed Sexton to level the scores at the break was poor reward for the work that had gone in.
The breakthrough came soon after the teams returned, Sexton again cross kicking for his wings, where he had spotted an obvious weakness. It paid off as full back Rob Kearney showed his game awareness, snatching the ball from Stuart Hogg’s grasp to give himself an easy jog to the line.
The Irish province could have added to the lead with O’Brien crashing through and offloading to Gordon D’Arcy, who was caught only a yard short with the support slow arriving.
Leinster were soon made to pay for the mistake as Glasgow eased their way back upfield, won a lineout on the visitors’ line and from the maul, Colin Gregor, the replacement scrum half, nipped over to level the scores and leave the game balanced.
Again, that brought the best out of Leinster, who stole the ball in the Glasgow 22, spun it wide to scatter the defence and then barged their way through the middle for Isaac Boss, to edge his way over the line and again restore the Irish lead.
There was a nervy end for the champions as Glasgow mounted a late wave of attacks. Glasgow had openings but ignored some and found Leinster players able to cover the rest despite losing O’Brien to a yellow card.
Scorers for Glasgow: Try: Gregor (62). Conversion: Weir. Penalty goals: Weir (6, 31, 48).
Scorers for Leinster: Tries: R Kearney (43), Boss (69). Conversions: McFadden (2). Penalty goal: Sexton, McFadden (2).
GLASGOW WARRIORS: R Lamont, T Seymour, S Hogg, G Morrison, C Shaw, D Weir, C Cusiter; J Welsh, P MacArthur, E Kalman, R Gray, A Kellock (capt), R Harley, C Fusaro, J Barclay.
Replacements: T Ryder for Kellock (blood, 31-41) D Hall for MacArthur (55), C Gregor for Cusiter (58), T Ryder for Gray (60), J Beattie for Barclay (60), T Nathan for Shaw (68), G Reid for Kalman (69), S Wight for Weir (74)
LEINSTER: R Kearney, D Kearney, F McFadden, G D’Arcy, I Nacewa, J Sexton, E Reddan; C Healy, S Cronin, M Ross, L Cullen (capt), D Toner, S O’Brien (sin bin: 75), S Jennings, J Heaslip.
Replacement: I Boss for Reddan (57), R Ruddock for Jennings (57), H Van der Merwe for Healy (64), E O’Malley for Kearney (64), N White for Ross (66), D Browne for Cullen (74)
Referee: N Owens (Wales).