France fell 2-0 to Sweden in their final Group D match in Kiev, bringing an end to their proud 23-game unbeaten run and sending them into a quarter-final with holders and reigning world champions Spain on Saturday.
Striker Olivier Giroud told reporters after Tuesday's loss to the Swedes that there had been "a shouting match" in the French changing room and Blanc did not dispute his version of events.
"When there's a victory, you accept things more and you're happier," he told journalists at a press conference in Donetsk.
"When you've lost, you're more hot-blooded. It got heated, but we all cooled down after a good shower.
"It kicked off a bit because all the players felt that everyone hadn't given everything. To win matches, you have to play them and play them well.
"I don't know if it's because we've got a fairly young squad. When you feel something, you have to say it, and it's not just down to the technical staff.
"They have to say things between each other, because it can be constructive. It shows that there's a reaction, and a bit of electricity. I hope that there will be some against Spain, but in the right sense."
A booking for Philippe Mexes against Sweden means that he will miss the match against Spain in Kiev, with Arsenal centre-back Laurent Koscielny expected to deputise at the heart of the French defence.
Koscielny was also asked about the flare-up in the French changing room and he said the players had already put it behind them.
"We said things to each other in the changing room, but what's said is said and we'll keep it in the group," he said.
"It was a complicated match, but the most important thing was qualification (for the quarter-finals). We would have preferred to qualify with a win, but these things happen.
"We have to turn the page. I think everyone's moved on now and we have to remain united, as we have been since the start of the training camp."
France could not ask for a more taxing last-eight assignment, with Spain boasting both the most prolific attack (six goals scored) and the meanest defence (one goal conceded) in the group phase.
Despite having witnessed France's long unbeaten run reach a sorry end, Florent Malouda said there was no time for self-pity.
"It wasn't the end of the run that was shocking, it was the way the run ended," said the Chelsea midfielder.
"We didn't look like the same team last night. You look back to South Africa two years ago (at the World Cup), the work we've done to get here, getting through to the quarter-finals...
"The way we gave everything up and played like a normal team who had come to play for fun in a tournament -- that's what was shocking.
"But it's better to end the run last night and then start a new one, and maybe win the competition."
France have also been drawn in the same group as Spain in qualifying for the 2014 World Cup and Malouda said Saturday's game therefore presents them with a double-pronged opportunity.
"We've done very well in our friendly games, against Germany, England and Brazil," he said.
"And we're in Spain's World Cup group. It's a good chance to show our ambitions. Spain are the model right now and we have to get as close to their level as possible."
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