To begin round three of the 2025 Six Nations, two sides with very different experiences of the word interim will go head to head.

For the visitors Ireland, with head coach Andy Farrell on British and Irish Lions duty, the temporary switch to his assistant Simon Easterby has not derailed their bid for a historic third consecutive Six Nations title.

Indeed, "seamless" appears to be the adjective of choice for the Ireland squad as back-to-back bonus-point wins have the reigning champions top of the table after the first block.

In contrast, while the Principality Stadium roof will guard against the elements for the 80 minutes, for the hosts it is impossible not to view the game in the wider context of the storm clouds gathered over Welsh rugby.

The Welsh Rugby Union used the down week to part company with head coach Warren Gatland, recent results accelerating a move that had been widely predicted to occur only after the championship concluded.

After demoralising losses to France and Italy, Cardiff's Matt Sherratt takes up the reins, although with a new contract at the Arms Park appearing to indicate he is not in the running to be named Gatland's permanent successor.

While Easterby himself has been talked about as a potential candidate - he distanced himself from such reports on Thursday - regardless of the length of Sherratt's reign, Wales fans will be hoping for some signs of recovery from a side who have lost their past 14 Tests dating back to the 2023 World Cup.

Change this weekend has not been limited merely to the coaching box.

Sherratt has made eight personnel switches from the side that lost against Italy last time out, along with two positional alterations.

Scarlets wing Ellis Mee, off the back of just 10 senior outings for his region, will make his Wales debut, while significantly there are returns for Gareth Anscombe and WillGriff John.

The former has not played in this competition since Wales clinched the Grand Slam six years ago, also against Ireland. The latter makes his Six Nations debut having not played international rugby for three and a half years.

For Wales, perhaps it was to be expected that a new broom would sweep clean.

But despite the winning formula utilised in the first two games, Easterby has made seven changes to his side too, with just two of them forced by injuries.

With the likes of James Ryan, Bundee Aki and Finlay Bealham held in reserve, and Hugo Keenan not involved at all, this is by some way the most callow line-up Ireland have named so far in this championship.

Replacement loose-head Jack Boyle will make his Ireland debut should he be used from the bench, while tight-head Tom Clarkson is set for his first start.

Jamie Osborne, Gus McCarthy, Cian Prendergast have never before featured in the Six Nations.

Injury, meanwhile, means Ireland go into a Test match without their influential captain Caelan Doris for the first time in four years.

As the number eight's incredible streak comes to an end, his positional replacement Jack Conan said the side's back row will be "under a huge amount of pressure" to compensate for his absence.

Hooker Dan Sheehan, meanwhile, will captain the side for the first time and believes the onus of leadership can be shared among the squad.

"We wish that Caelan wasn't injured but someone had to step up," said the 26-year-old.

"I was asked on Monday and I was absolutely delighted to take that responsibility. It's something I've enjoyed so far.

"This team sort of runs itself with the leaders that are in it. There are a handful of people who could have been named captain - Pete [O'Mahony], Tadhg Beirne, Jamo [Gibson-Park], Jack Conan.

"A lot of them have huge amounts of leadership and they help to run the week as well. Obviously my name gets the 'c' beside it but we know in our group we rely on a lot of people."

With the sides in such contrasting form, Ireland's unforced changes may lead to more in Wales thinking that their visitors have not arrived with full focus.

Accusations of arrogance have swirled in the build-up after an Irish radio station debated whether their side would be victorious if they took the field with only 12 or 13 players.

While hardly representative of the entire nation, or indeed the team, the clip was shared widely on social media and used as an example of a developing hubris around a side who have lost just twice in their past 20 Six Nations games.

For his part, Easterby - who still lives in Wales - is not underestimating the opposition at a ground where Ireland did not win a Six Nations game between 2013 and '23.

"I think Wales are always dangerous," he said.

"You can read into whatever around the results and performances, but at home in the Principality they're a different beast. We have to respect that."

Besides, whatever about the looming prospect of France back in Dublin next time out, Ireland should have learned their lesson last year in relation to looking too far ahead.

When shooting for the history of consecutive Grand Slams, they were upset by England in Twickenham last March, with the thrill of winning the title against Scotland a week later somewhat diluted by the lack of a clean sweep.

Now aiming to become the first side to win three outright Six Nations titles in a row, a slip on Saturday would be filed in the same category and viewed as evidence of a lesson not learned.

As Conan rhetorically asked the media this week: "If we don't go out and perform this weekend, then what does that say about us?"