Manager Giovanni Trapattoni rated his side's chances as "50-50" in Paris after Saturday's defeat in Dublin.
The last time Ireland upset a higher-ranked team for a competitive win was eight years ago when a Jason McAteer goal beat the Netherlands en route to the last of the country's three World Cup appearances.
However, you need to go back 22 years to find the last away qualification upset when another single goal helped Ireland past Scotland in Glasgow and ultimately to their first international tournament at the 1988 European Championship.
"We have played only the first half. I think we can score on goal in Paris. We must have confidence," a positive Trapattoni told a news conference after the first leg.
"We must play with the same attitude, put more pressure on them. We cannot allow them to play at their tempo."
Ireland ran out of steam in the second half on Saturday and despite not being out of the tie, do not play a game suited to chasing a game in someone else's backyard.
Nor do they have any recent results to back up coach Trapattoni's optimism, having drawn six of 10 games in their unbeaten group campaign with their two away victories coming in Cyprus and against Georgia on neutral soil.
Trapattoni intends to stick with the same team on Wednesday as he hopes to tear up the two-decade old form book but that will mean pacy Celtic winger Aiden McGeady, one of Ireland's few potential game breakers, will again be on the bench.
Should Ireland fail to trouble the French goal, calls will also resume as to why another of Ireland's few creative players, Sunderland's Andy Reid, was once more omitted from the squad.
Trapattoni remained resolute that his side showed enough on Saturday to prove they can turn the tie around.
"We showed all the people we can score and must go to Paris with this hope," he said.
"We must be positive. We have shown in other games we can score and can perform when we are not expected to win."
