The win -- secured with seven tries including a brace from fly-half Johnny Sexton -- means Ireland currently top Pool A with 16 points, ahead of Japan's 14 and Scotland's 10. Japan and Scotland are due to meet in Yokohama on Sunday, though the game remains in doubt because of the devastating storm.
Typhoon Hagibis made landfall on Saturday night local time as hurricane-force winds battered infrastructure and killed two people. Tokyo and nearby Yokohama are at the center of the storm.
Weekend games between New Zealand and Italy as well as France and England had already been canceled Thursday, with Saturday's Formula One qualifying at the Japanese Grand Prix also canceled.
If Japan and Scotland are not able to play, the game will be declared a 0-0 draw with both teams receiving two points. Ireland would then play South Africa in the next round as group winners with Japan taking on New Zealand.
READ: Typhoon Hagibis makes landfall in Japan, leaving at least one dead
A resounding win
Not that Ireland were concerned with that for the 80 minutes against Samoa in Fukuoka, western Japan, some 1,100 kilometers away from Tokyo. Having already lost once in this tournament -- a 19-12 defeat to Japan that few saw coming -- coach Joe Schmidt's team would have been eager to lay down a marker ahead of the knockout phase.
The first score came after just three minutes when captain and hooker Rory Best finished from the back of a driving maul.
Winger Jacob Stockdale received the Samoan restart and charged up the field where he was clattered by Seilala Lam. The referee deemed the challenge illegal and replays justified the brandished yellow card for a high shoulder.
The Irish forwards enjoyed the man advantage and dictated the early exchanges. It was another front-rower who dotted down when Tadhg Furlong scored his second try of the competition on 10 minutes. The burly prop gave a show-and-go before finishing from eight meters out.
The game threatened to become a rout when Sexton -- who scored 18 points on the night -- was on the receiving end of a delightful inside ball from his fullback Jordan Larmour and had an easy run to the line. Sexton converted and the score read 21-0 after 21 minutes.
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That trio of tries finally galvanized the Pacific Islanders who won a line out in Irish territory and worked through several phases. Captain Jack Lam burrowed and retrieved the ball two meters out and was too strong for his opposing No. 8 CJ Stander to score.
That proved to be a momentum shift and the pendulum swung even further towards the men in blue when Ireland's inside center Bundee Aki was shown a straight red for a dangerous tackle on fly-half Ulupano Seuteni. There appeared no malice in the act, but referees are under strict instruction to harshly punish errant shoulders that make contact with the head or face.
Ireland were forced to consolidate with a man down but grew back in the game as the halftime whistle approached. The bonus point for four tries scored was made safe just before the interval when Sexton had his second after a well worked move from a scrum. He missed the extra points from the conversion as he led his team into the break 26-5 ahead.
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Sterner tests await
Though depleted in the backs, the Irish forwards continued to dominate and they folded the Samoan pack from a scrum on 48 minutes. The resulting penalty was quickly taken and neat interplay saw Larmour achieve a deserving five-pointer. Sexton slotted the extras in his last act of the match.
Two more Irish tries -- from Stander and replacement Andrew Conway -- meant the 2018 Six Nations champions registered their highest score in Japan.
Ireland will face tougher opposition in the next round as it seeks to reach the semifinals of a World Cup for the first time in its history. New Zealand's All Blacks or South Africa's Springboks await. Which one will be determined by the eventual outcome in Japan and Scotland.
READ: Typhoon Hagibis makes landfall in Japan, leaving at least one dead Rugby World Cup 2019 in pictures Ireland will face tougher opposition in the next round as it seeks to reach the semifinals of a World Cup for the first time in its history. New Zealand's All Blacks or South Africa's Springboks await. Which one will be determined by the eventual outcome in Japan and Scotland. READ: Typhoon Hagibis makes landfall in Japan, leaving at least one dead Ireland will face tougher opposition in the next round as it seeks to reach the semifinals of a World Cup for the first time in its history. New Zealand's All Blacks or South Africa's Springboks await. Which one will be determined by the eventual outcome in Japan and Scotland.
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