Will they ever make it easy for them-selves?

Must they always do it the hard way? After 40 minutes of this astonishing match at Scotstoun, the only question on the lips of the crowd was how much longer it would take Glasgow Warriors to get their try-bonus point. They had three tries on the board, Leinster on the rack and a 16-point lead that could easily have been much more. To all intents and purposes they had the game won.

And yet, as the game passed the 80-minute mark, the Warriors trailed by one point. Staggeringly, they had somehow managed to ship 14 points in the space of two mad minutes as Leinster replacements Jack McGrath and Tom Denton piled over for tries and Jimmy Gopperth converted both. As an exercise in whipping a defeat from the gnashers of victory, it was up there with the most spectacular.

Yet to their immense credit, Glasgow worked their way back upfield in the few minutes they had left. They won a penalty in the left corner, chose to go for the line-out, but were held out. Then, though, in the last play of the game, with the clock already far past the 80th minute, they won another penalty as half the Leinster team rushed off-side. Niko Matawalu feinted as if to run the ball, but fortunately wiser counsel prevailed. Up stepped Stuart Hogg to stroke the ball over, and Glasgow had the win that few would suggest they did not deserve.

"I was disappointed we gave them the chance to get within six points," said Warriors coach Gregor Townsend of Leinster's first try. "There was a period of stalemate in the second half, tired bodies and the first game of the season, but we want it to be accurate and high tempo.

"We needed to play to win the game, but if you are soft in defence, as we were at times in the second half, and our discipline wasn't great, these things happen. But I have to say that the character the players showed, the effort they put into the whole game, to come back, win the ball in the face of tough tackling was excellent."

Yet as desperate and last-ditch as it was, and however painful some of the review process will be, Glasgow will take huge heart from the simple fact that they beat the reigning champions and the team who pipped them to the PRO12 title in last season's Dublin final. They can also reflect with satisfaction on that opening period, when they played mesmerising and wonderfully effective rugby that left Leinster chasing shadows.

At the heart of that effort was the high-tempo off-loading game that has been a Glasgow hallmark in recent seasons but which may never have been played better. They unleashed themselves at Leinster, moving the ball slickly, cleverly and at pace. The Sky TV camera operators who were covering their first Guinness PRO12 game, will probably be relieved to know that things don't always happen this fast.

Certainly it was more than Leinster could cope with. After the gentle preliminaries, Glasgow opened up, sending pods of players spearing through the Leinster defence. Whenever the Irish players seemed to have plugged one gap, another opened and a Glasgow runner would shoot through it. The rewards came fast and spectacularly. With 17 minutes gone, the Glasgow scrum sent the Leinster pack scuttling back over their own ball, seized possession and released a posse of payers down the narrow side. Alex Dunbar, Tommy Seymour, Chris Fusaro and Henry Pyrgos combined in a flurry of movement, and Peter Horne finished off with a try.

Six minutes later, this time on their own ball, the Glasgow set-piece again overwhelmed their struggling opponents. Again, they attacked in waves and again their momentum carried them right up to the line. Leinster did well to stop the move there, but the respite was brief. Josh Strauss probed round the ruck and Jonny Gray thundered over to score.

Scotstoun was in tumult by this point, and the joy of the Glasgow fans was even less constrained a few minutes later when Strauss grabbed a loose ball a few metres outside the Leinster 22 and galloped all the way to the line. Thirty minutes, three tries, a 19-0 lead. The game was all but over.

Except in the minds of Leinster. As wretched as they had looked in the first half-hour of competitive rugby post-Brian O'Driscoll, they girded themselves splendidly and showed the Scotstoun crowd what champions are made of. By half time they had clawed back three points with a penalty by Ian Madigan, and they took three more in the 53rd minute when Gopperth clipped over another.

The mathematicians in the ground realised that two converted tries would give Leinster a win. And some of them were wearing Leinster shirts. McGrath was thrust over near the left corner in the 73rd minute, and Denton near the right in the 75th when Glasgow were horribly dozy at a line-out. Just as well that Hogg was wide awake when given the chance to turn the tables at the end.

Glasgow: P Murchie; T Seymour, M Bennett, A Dunbar (S Hogg 48), L Jones; P Horne (S Lamont 55), H Pyrgos (N Matawalu 60); A Allan (G Reid 53), F Brown (P MacArthur 53), E Murray (R De Klerk 65), L Nakarawa (T Swinson 65), J Gray, R Harley, C Fusaro (A Ashe 60), J Strauss (Captain).

Leinster: Z Kirchner ; F McFadden, B Macken, N Reid (I Madigan 1min), D Fanning; J Gopperth, I Boss (L McGrath 65); C Healy (J McGrath 40), S Cronin (B Byrne 68), M Ross (T Furlong 53), B Marshall (T Denton 53), M McCarthy, D Ryan, S Jennings (K McLaughlin 70), S O'Brien (captain).

Referee: N Owens (Wales)

Attendance: 5725