Bernard Jackman believes Leinster’s total superiority over the other three provinces could represent a “slippery slope” for Irish rugby.

Leo Cullen’s side maintained their 100% record in the United Rugby Championship over Christmas, their experimental side accounting for a brave Connacht in the Aviva Stadium, before the big guns returned for the 28-7 victory away to Munster in Thomond Park.

Munster, in a state of flux in the coaching booth since the departure of Graham Rowntree early in the season, did grind out an important win over Ulster in Kingspan Stadium. However, they were comfortably over-powered at home to a Leinster side, now operating on a completely different plane.

The decision to rest first-choice out-half Jack Crowley for the visit of their biggest traditional rivals was taken by some as damning evidence of their belief that the game – once the blue riband fixture in Irish club rugby – was now a write off.

“I was chatting to a lot of Munster fans before the game and they were so disappointed that Jack Crowley was out before the game,” Jackman said on RTÉ 2fm’s Game On.

“Their whole thing was… is that what we’ve become?

“Are we a team who rests players in the Champions Cup? Are we a team who rests players against Leinster? Not because we think we can win anyway, but because we don’t think we can win.

“I’m not saying that’s why Jack Crowley didn’t play and obviously there’s an IRFU mandate about how many games he plays, but certainly the fans felt short-changed.

“In fairness to the Munster players, their effort was outstanding. They just didn’t have the tools. They didn’t have the quality, the size, the power to go toe-to-toe with a Leinster team.

“And the challenge is, if that gets into the fans’ minds, they don’t necessarily buy those tickets. That match isn’t sold out next year.

“And then you’ve got more financial issues and you start to drift away. And the team’s expectations start to drop as well. And the standards that they set drop. That’s a slippery slope to go down.”

Rowntree had guided Munster to a surprise URC win in his first season as head coach, stunning the Stormers in the Cape Town decider to claim the title for the first time in 12 years.

However, midway through the 2023-24 campaign, they suffered a body-blow with the loss of South African lock RG Snyman to Leinster, a transfer which generated outrage among the Munster support. In the off-season, it was confirmed that Jordie Barrett would be joining Leinster, further copper-fastening their dominance as they chased Champions Cup success.

Munster, meanwhile, have slumped but Jackman believes that a few high profile imports could help turn the tide for the other Irish provinces, especially with the IRFU well positioned in a buyers’ market.

“There’s nothing wrong with having one province a little bit stronger than the others. And it’s always most likely going to be Leinster, because of the population and the financial (aspects), but I think we still need to try and have four strong provinces.

“The IRFU are in a very healthy state financially. And the game is in a poor state (globally).

“So to recruit now for next year is cheaper than it’s ever been. You could get some quality players.

“You have three clubs in England that went out of business, the salary cap in England is quite low. The French clubs only want the best of the best. A lot of South Africans are keen to get to this side of the world and get euro or sterling. That’s a lot of good players on the market.

“The problem is it’s not just money. It’s how many non-Irish qualified players are you allowed and at the moment, that’s quite stringent, it’s quite strict. And that’s where they’re caught.

“The long-term future has to be that they develop their own players in their own academy systems. But short-term, those high quality foreign players can turn the dial.

“Leinster have the luxury of being able to play Snyman and Barrett off the bench. The influence they would have for a Connacht or an Ulster or a Munster from the start would be massive.”

Jackman also touched on Leinster’s recent style-change, with Jacques Nienaber introducing a distinctly Springbok sensibility into a side previously renowned as a byword for flair.

With Ireland soon to embark on a three-in-a-row tilt in the Six Nations following a rather indifferent November series, Jackman discussed how Leinster’s gear shift could effect a national team which is heavily dependent on their players.

“I’m sure for Simon Easterby, who’s new to this job, it’s a little bit worrying. The test will be can he get these players in and get them with their Ireland caps on and that they don’t have the same habits.

“That’s not really how it’s worked in the past for Ireland. There has been an alignment (between provinces and national team).

“But, to be fair, that’s what most other coaches have to do. With the French team, you have the Toulouse influence, the Toulon influence, the Racing influence. Most other coaches have to marry different philosophies when they’re getting ready for the Six Nations.

“We are very different. We’re like Scotland to some extent, who are underpinned by the Glasgow team. Ireland, even though we’ve got four provinces, the majority of them are Leinster players.

“That does present a challenge for Simon Easterby. How he adapts to that and how those players adapt will have a massive influence on whether we’re successful in the Six Nations.”