The beauty of this game is that it can change so quickly.
Leinster reside in fourth, just five points away from PRO12 League leaders Connacht, with champions Glasgow one away in fifth.
"One look at the table will tell you how important it is to Glasgow and Leinster this weekend," said Eoin Reddan, on the eve of his 125th cap for The Blues.
Coach Leo Cullen makes eight changes from the marked improvement shown against Ulster with natural leader Rhys Ruddock taking over the captaincy.
The back row is a fine blend of power, energy and agitation at the breakdown.
At number eight Jordi Murphy makes his play for finding form and Josh van der Flier looks to continue building his reputation as a non-stop ball of action.
The front row is made up of recovered concussion victim Richardt Strauss and two props, Cian Healy and Martin Moore, working their way back to consistency.
None started last week and all should be ready to fire their best shots in what is certain to be a caustic environment.
There must be a concern at second row where Tom Denton and Mike McCarthy look to be over-matched with Jonny Gray and the Fijiian ball-handling phenomenon Leone Nakarawa.
Out the back, Ian Madigan will step up at fly-half with an aim to remind everyone of his virtues there with assistance from Reddan, the veteran in pursuit of higher standards.
Full-back Rob Kearney returns from his hamstring to complete a solid back three with brother Dave and Zane Kirchner.
Ben Te'o and Luke Fitzgerald are paired again in the centre in what is a combination that offers all sorts of possibilities.
The fact remains that Leinster have threatened far more than they have delivered to this point in the season.
There was plenty of grit and determination in the narrow 8-3 win over Ulster.
"While we were glad to get the win, we know there are things we could be better at," said the scrum-half.
The blight of not being able to turn territory into tries in the big games is a worry.
"Hopefully, we'll improve this week and be better again at the weekend because we'll need to be against Glasgow."
The collective commitment and understanding of all involved suggests the flaws are being ironed out.
"There's a good level of honesty there from the coaching staff to us about what we need to improve and that's helping us.
"It's making sure that we know where we're at every week, and when you know where you're at you've a chance of moving forward and that's what we're doing."
However, Leinster have yet to truly transfer the positivity of practice into the match arena.
There is no better place to bring all the aspects of the game together than at a hostile, sold-out Scotstoun.
"It'll be a very tough fixture," noted Reddan.
"We need to be very good over there to get a win.
"I think it'd be great for the squad if we managed to do that."
Gregor Townsend has taken Glasgow on a journey of discovery and achievement which means they fear no one in the PRO12.
The Warriors had to suffer the same fate as Leinster in that they were bulk providers to their national squad for the World Cup.
There was even an understandable sense of grievance felt around Scotland for the way they exited in controversial fashion to Australia.
This will have further fuelled the players confidence that they can compete with the best in the world.
Moreover, they have the distinct advantage of coming back to the same coach, the same calls, the same systems they have been working on since the summer of 2012.
Townsend hands a full debut to hooker James Malcolm, 21, in his third appearance of the season. This is a real vote of confidence.
"Anytime you play Leinster is exciting," he remarked.
"They've been the best team in our league over the last five or six years and they've got real quality."
Leinster were not the best team last season or over the first eight rounds.
There are logical reasons for that with so many changes and the necessity for rotation.
They are looking for that one occasion when all they have been working towards comes together.
It couldn't happen at a better time with an angry Toulon waiting just around the corner to make amends for their European embarrassment.
Glasgow: S Hogg; T Naiyaravoro, A Dunbar, P Horne, T Seymour; D Weir, M Blair; R Grant, J Malcolm, S Puafisi, L Nakarawa, J Gray (capt), J Strauss, S Favaro, A Ashe.
Leinster: R Kearney; Z Kirchner, B Te'o, L Fitzgerald, D Kearney; I Madigan, E Reddan; C Healy, R Strauss, M Moore, T Denton, M McCarthy, R Ruddock (capt), J van der Flier. J Murphy.
Glasgow v Leinster today (live 3pm, Sky Sports 1)