France midfielders Blaise Matuidi and Rio Mavuba are fully aware how much is at stake as Les Bleus conclude their bid to reach next summer's World Cup.
Matuidi described the Brazil showpiece as a "once-in-a-career" opportunity while Mavuba acknowledged the two-legged play-off against Ukraine on Friday and Tuesday comprises the most important games since Didier Deschamps took charge of the national team.
Paris St Germain star Matuidi told L'Equipe: "We absolutely need it. A World Cup does not come along every day, especially one in Brazil.
"It's a dream for everyone who likes football, it only comes around once in a career. Today we have that opportunity.
"I hope we can negotiate (Friday's away leg) and that everyone in France is behind us for the return to help us qualify."
Lille player Mavuba, who last featured for his country again Belarus last September in their second game of the current qualifying campaign, said: "I have returned at a good time, for the two most important games of the Deschamps era.
"We are desperate to qualify for this World Cup, that was the objective from the start. We will do all we can to do that."
Mavuba watched from afar as France finished second behind reigning world and European champions Spain in a group also containing Finland, Belarus and Georgia.
And he said: "It has been good. We have to go through the play-offs but given the group we landed in, that was practically determined.
"The play-offs are not new to us. It was the same in 2010. The most important thing is still to qualify."
France expect to have Hugo Lloris available for the first leg in Kiev, which comes almost two weeks after the Tottenham goalkeeper suffered concussion against Everton.