Ireland face an uphill task in Paris on Wednesday but star midfielder Damien Duff thinks the upset can be achieved. The Republic trail 1-0 on aggregate after a Nicolas Anelka goal gave France victory in Dublin on Saturday evening.
But Fulham midfielder Duff believes a shock win can be pulled off at the Stade de France.
Asked if it would be the nation's greatest result, Duff said: "Ever, without doubt.
"We have taken an awful lot of positives out of Saturday. Other people may not have but we think we can go there and do it."
He said: "I was actually thinking about that this morning first thing when I woke up.
"I don't think I have gone away behind looking to resurrect a tie so to speak, so it's new to me and I am sure it's new to an awful lot of the lads.
"We just have to go there and enjoy it. We still think we can do it, so bring it on.
"We have obviously given ourselves an uphill task. Away goals are a massive thing in football but, if we go over there and nick one, it is game on again.
"We are all confident we can go and do it. You have to be."
Meanwhile French star Patrice Evra hopes Irish fans will not overwhelm French support in Paris after reports that up to 25,000 Irish might travel. “I hope not,” he said to France Football. There have been widespread reports that French fans thinking the French are through to the World Cup may stay home “I do not know what caused it or who, but for me it's not normal ... But I trust our fans.
“I do not dream of seeing the Stade de France like this: if it’s a requirement, then so be it! It would be logical that the French people awoke for such a World Cup match - we all want to go.
"To see all the [French] flags at Croke Park it affected us. Thank you to the 6,000 French present in Dublin - it was spoken of between us, it affected us,” he revealed.
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