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Increasingly windy tomorrow. After a mainly dry morning, a band of rain will extend across the region during the afternoon. Mild with highs of 12 to 14 degrees.
Farrell favouring 'mobile' pack
Andy Farrell's team selection for Saturday triggered a great deal of comment and hand-wringing. Not so much due to specific gripes with the XV itself and more to do with what its composition said about the state of the game in Ireland.
Twelve of the starting XV are graduates of the Leinster academy - including the only two current Munster players in the line-up - with the remaining three New Zealand born. Perhaps never before has the Irish team been so lop-sided in its dependence on one province.
In 2021, the Ireland team increasingly consists of the products of the Leinster school system plus a smattering of project players, with the odd freakish 'outlier' tossed in.
The selection inevitably provoked an outpouring of despair and where-did-it-all-go-wrong theorising from some, particularly those down south, but from the denizens of the east, there was a backlash against the backlash, with some bemoaning what they saw as the 'petty, parochial' reaction to the selection. ("We're all Ireland after all, guys").
Out west, meanwhile, there's annoyance that Jack Carty's fine form in 2021 hasn't been rewarded with a call-up.
It's worth pointing out that Conor Murray and Iain Henderson may return to the fray for next week, giving the starting XV a more rounded geographical flavour.
Former Munster and Ireland lock Donal Lenihan didn't dwell on the geographical considerations and declared Farrell's selection "exciting", particularly focusing the highly mobile pack selected.
From numbers 4-8, Ireland look especially strong, with Lions Tadhg Beirne and Jack Conan both in the side, with Josh van der Flier, Man of the Match against Japan in July, also selected.
In the backline, Hugo Keenan, consistently impressive since his elevation to the role of starting XV, survives the threats to his position.
James Lowe's star fell rather precipitously during the Six Nations, his jittery defence being blamed for the concession of tries against Wales and France. A hideously error-ridden performance against Scotland saw him sit out the resounding win over England in Round 5.
He's in the side again, characterising the Six Nations as an "awesome learning curve", from which he has come back stronger.
As far as providing background for this contest, we could just dust off much of what was written during the summer. Prior to July, Japan hadn't played in Dublin since November 2000; by Sunday, they'll have played here twice in four months.
Played in front of 3,000 spectators - the first time the Aviva had welcomed crowds of any sort since the pandemic began - the July match was a humdinger, chiefly thanks to Japan's thrilling and flamboyant running game. The visitors rustled up four tries, a couple of them absolute stunners, in particular the second and third scores, largely created by the clever decision making/kicking game of Yu Tamura.
Ireland, however, ground out a win in the end, two tries in four minutes in the third quarter from Josh Van der Flier and Jacob Stockdale proving crucial. Saito's try on 57 minutes reduced the deficit to a point again but Ireland successfully closed up the contest from there, Joey Carbery notching two penalties to leave an eight-point margin at the finish.
Japan's most recent outing, their only one since Dublin, was under two weeks ago at home to Australia in Oita. Another moral victory was notched against a resurgent Wallabies, who'd just finished second in the Rugby Championship.
Tries from Lomano Lemeki and Ryoto Nakamura helped the hosts trail by just four points as the match entered the final five minutes, though a late score Connal McInerney gave the Aussies a 32-23 win at the end.
The electric pair of Kotaro Matsushima and Tamura are back in the team for Saturday, having missed the Wallabies game. Winger Dylan Riley and blindside flanker Ben Gunter are the only new faces to the team from the side that lost in the Aviva last time out.
After their sensational progress since the last World Cup, Japan have been left somewhat marooned during the Covid disruption. Remarkably, this is only their fourth match since South Africa eliminated them at the quarter-final stage in 2019.
Sexton joins the ranks of the centurions
Four months after his 36th birthday, Sexton is still trucking, possibly planning on cramming in another World Cup tilt before he packs it up. It's 12 years since his Donnybrook debut against Fiji - made a few months after he had replaced an injured Felipe Contepomi to kick Leinster to victory in the 2009 Heineken Cup.
He is the seventh Irish player in history to hit treble digits, after Brian O'Driscoll, John Hayes, Ronan O'Gara, Paul O'Connell, Rory Best and Cian Healy.
A tense moment from the Zoom press conference with Peter O'Mahony - no stranger to tense moments in press conferences - ahead of the July game. One persistent member of the press corps was incredulous that the team hadn't sat down and watched the infamous 2019 RWC pool game all over again.
O'Mahony, it's fair to say, was incredulous at this guy's incredulity.
"No, we haven't watched it. Do you think we sat down and watched the full 80 minutes again, like? With thirteen uncapped players!" he said, in a tone of increasing annoyance, bringing an abrupt end to the Q&A.
Last five matches
2021: Ireland 39-31 Japan, ST, Dublin
2019: Japan 19-12 Ireland, RWC, Shizouka
2017: Japan 13-35 Ireland, ST, Tokyo
2017: Japan 22-50 Ireland, ST, Shizuoka
2005: Japan 18-47 Ireland, ST, Tokyo
Ireland: Hugo Keenan; Andrew Conway, Garry Ringrose, Bundee Aki, James Lowe; Johnny Sexton, Jamison Gibson-Park; Andrew Porter, Rónan Kelleher, Tadhg Furlong; Tadhg Beirne, James Ryan, Caelan Doris, Josh van der Flier, Jack Conan.
Replacements: Dan Sheehan, Cian Healy, Finlay Bealham, Iain Henderson, Peter O'Mahony, Conor Murray, Joey Carbery, Keith Earls.
Japan: Kotaro Matsushima; Dylan Riley, Timothy Lafaele, Ryoto Nakamura, Siosaia Fifita; Yu Tamura, Yutaka Nagare; Keita Inaki, Atsushi Sakate, Jiwon Gu; Jack Cornelsen, James Moore; Ben Gunter, Pieter Labuschagne (c), Kazuki Jimeno.
Replacements: Yusuke Niwai, Craig Millar, Asaeli Ai Valu, Yoshitaka Tokunaga, Tevita Tatafu, Naoto Saito, Rikiya Matsuda, Ryohei Yamanaka.
Follow Ireland's November internationals v Japan, New Zealand and Argentina via our live blogs on RTÉ.ie/sport or the RTÉ News app, or watch live on RTÉ2 and RTÉ Player. Live commentary on RTÉ Radio 1.