Aki was sent off in the 29th minute for a dangerous high tackle on Ulupano Seuteni, leading with his shoulder and making contact with the flyhalf's face. An independent judicial committee rejected Aki's appeal against the red card and imposed a three-match ban, which would rule the midfielder out of contention through the Nov. 2 final.
"Although the tackle occurred quickly, the player's tackle height was high and it was accepted he did not make a definite attempt to change his height in order to avoid the ball carrier's head," the panel said.
The dismissal made him the first Ireland player to be red carded in a Rugby World Cup. Despite being down to 14 men for 50 minutes, Ireland went on to win 45-7 and finished second in the group behind Japan.
That sent Ireland into the toughest of the quarterfinals possible, against the defending champion New Zealand All Blacks at Tokyo Stadium. If Ireland is knocked out before the World Cup final, the balance of Aki's sanction will be transferred to his club.
Ireland head coach Joe Schmidt said before the ban that he'd be ready to prepare a lineup missing the strong-running midfielder. "It's all split-second stuff. But once it's a red card you sense a loss of control over what happens next, no matter what you present," Schmidt said. "I certainly feel for Bundee, he's pretty devastated that any further participation is potentially at risk."
Flyhalf Jonny Sexton on Monday said Ireland was positive about overcoming some setbacks in the group stage, including the upset 19-12 loss to Japan. At the World Cups in 2011 and 2015, Ireland was dominant in the group stage but then lost quarterfinals to Wales and Argentina. Despite a knockout game against New Zealand, which has won the last two titles and is a three-time champion overall, Sexton is confident the Irish can reach the semifinals for the first time.
"There's been some negativity around us and we'd feel that's been pretty strange," he said. "But we're really confident in how we're building. I'm hoping that having lost a pool game that we've got that (bad) quarterfinal performance out of our system that we've had in other tournaments.
"The difference now is we're not favorites going into this quarterfinal whereas we were in the last two. So we're building nicely, we haven't hit our best performance yet and we need to get close to that to get the right result on Saturday."
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