Coach Matt O'Connor is adamant Leinster's season could be "largely defined" by what happens over the next two weekends.
Conor O'Shea's dangerous Harlequins stand between the three-time European Cup winners and lead position in Pool Two of the Rugby Champions Cup.
For the moment, O'Connor will take heart from that fact that Leinster were able to subdue the fired-up Ospreys 18-12 at the RDS with a transformation in intensity from the dross served up in Treviso.
"It's always good to get a hit-out of that standard against a very good Ospreys side, even down on personnel," said O'Connor.
"They were abrasive, physical and they made us work very hard. There are some good review materials there.
"The main ones would be to put together a little more pressure in the opposition half, whether that would be exit strategy or executing from set-piece strategies.
"We probably didn't put them under enough pressure, especially in the first half when you need to get into their half. We needed to control the ball a little better and force them to be more accurate in defending us."
Overall, Leinster will be content to have taken 12 points from their last three League matches to put them right on the coat-tails of the leaders.
"We knew there was a good opportunity coming into these three games and thankfully we got two wins and a draw," he reviewed.
"The season will be largely defined by the next two weekends and the group understands that. We need to make sure we control everything to make sure we're in the right spot in two weeks' time."
Leinster had to cope with genuine disruption in the lead-in on Saturday as Mike McCarthy failed his return-to-play protocols and replacement scrum-half Isaac Boss couldn't beat off a bug.
Former Leeds Carnegie lock Tom Denton jumped right on for his third start of the season and Luke McGrath shed the captaincy from the British & Irish Cup match earlier in the afternoon to take his seat on the bench.
The Ospreys weren't exactly bright and breezy about their options without seven Wales internationals and 12 others giving them a rather unfamiliar appearance in places.
It could have been billed as high balls at high noon as Ospreys fly-half Sam Davies launched one or two which Zane Kirchner and Jimmy Gopperth returned with interest. Then, Ian Madigan got his left leg caught in an awkward position and was tended to as Davies picked up the first penalty of the evening in the sixth minute.
The versatile Ireland international was no sooner on his feet than he was taking the ball straight and hard enough into wing Aisea Natoga to draw a penalty for a high hit, levelling it up from 40 metres in the tenth minute.
Natoga took out Gopperth in the air, prop Dmitri Airhip needlessly worked his way around the side of a maul and Martin Roberts hammered the ball directly to touch as the Ospreys discipline faltered.
This all released the pressure on Leinster and handed them territory that wasn't really of their own taking.
Madigan was dead-eye-Ian from the right to put Leinster in front, very much against the run of play.
The home side's defence was intense and it loaded pressure onto the Ospreys to force the pass. The trademark Leinster surge came hot and heavy. Referee Marius Mitrea spotted Tyler Ardon slowing down ball illegally at a ruck. Madigan made him pay the price from the left for 9-3.
There was danger in the air. Davies had another cut. Gopperth was harshly penalised and Davies notched his second three.
The Welsh men got the rumble on from a maul. It travelled with ominous ease until halted, turned back and turned over by Leinster.
Torrid defence will only get you out of trouble for so long. The Ospreys came again. Mitrea whistled at the ruck. Davies tied it up in the 38th minute. The interval provided the respite to recover, rethink or reapply the game plan because they were back where they started - all square.
Quite simply, Leinster did not have enough ball to get going. They had to win it to keep it. They would have to do so without their goal-kicker Madigan, retiring with a foot injury, to herald the introduction of Gordon D'Arcy. Martin Roberts almost unlocked Leinster with a short ball to Natoga, correctly deemed forward by Mitrea.
Jack Conan shrugged off Hanno Dirksen and Dave Kearney bulled onward to within sniffing distance of the whitewash
Leinster were finding their rhythm. At last. They did enough to dig up a penalty for Gopperth to make it 12-9 in the 53rd minute.
Kirchner over-cooked a long, low ball to invite pressure back. And the runners came in waves. Eventually, hooker Byrne went off his feet coming through a ruck for Davies to square it on the hour.
The Ospreys continued to show the confidence they have garnered from rising to the top of the League, while Leinster looked to move by stealth.
Gopperth fastened onto a loose ball to set in motion a counter from deep with a willing Dominic Ryan on his shoulder. It led, indirectly, to the lead penalty from Gopperth when prop Cai Griffiths went to ground at a ruck.
The issue was sealed when the pack powered on at a scrum and Gopperth chipped over the final three. This outcome may just knock the wind from the Ospreys sails as they have played well against Ulster and Leinster away from home without any significant reward.
The specialist number eight is just beginning to show what he can do from that position.
It came right at the death when the Leinster scrum went into overdrive put three points on a plate for Jimmy Gopperth.