Ireland are still waiting to hear on the severity of the injuries to Sexton and O'Connell although it appears likely that the latter's World Cup - and as a result his Ireland career - is now over.
Late tries from Lions duo Rob Kearney and Conor Murray saw off the French at the Millennium Stadium.
Victory means Ireland will take on Argentina in their quarter-final while defeated France will take on the All Blacks.
New Zealand - who welcome the Lions in 2017 - finished with a perfect four victories from four in pool play as they saw off Tonga.
Richie McCaw was rested to continue his recovery from the leg injury sustained against Georgia while Nehe Milner-Skudder crossed twice in the victory.
Wales are also in the quarter-finals but defeat to Australia means Warren Gatland's side have a tough last-eight match-up with South Africa.
Their already-threadbare backline suffered another injury blow when Liam Williams was ruled out with a foot injury and the Wallabies produced a fine defensive stand with 13 men to hold off Sam Warburton and co.
Scotland are also into the quarter-finals but they were made to work extremely hard for victory over Samoa and will now face a tough clash with Australia.
England's involvement in this year's World Cup is over however, they become the first host nation to fail to make the knockout stages.
They did at least finish off on a high though, running in ten tries against Uruguay to claim a comprehensive 60-3 victory.
But all attention now turns to next weekend and the quarter-finals as the World Cup approaches the business end.
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