Brice Dulin scored a try with the final play after the 80-minute mark to earn France a thrilling 32-30 victory over Wales at the Stade de France that denied their opponents a Grand Slam and keeps their own Six Nations title hopes alive.
Wales led 30-20 with 10 minutes to play in Paris and had a one-man advantage after Paul Willemse was sent off, but Taulupe Faletau and Liam Williams were both sin-binned in quick succession and that sparked a remarkable turnaround.
Dulin touched down in the 82nd minute to secure a victory that leaves France needing another bonus-point win at home to Scotland next Friday – a fixture pushed back due to a coronavirus outbreak in their camp – to finish above Wales.
The incredible late drama followed an equally lively first half in which four tries were shared, but Wales' failure to see out the job means their fate is no longer in their own hands.
Fabien Galthie kept faith with the same XV that narrowly lost to England and was rewarded by a fast start from his side as Romain Taofifenua opened the scoring inside five minutes from a quickly taken line-out.
Gareth Davies was denied by a sublime try-saving challenge from Charles Ollivon, but Wales were level two minutes later when Dan Biggar powered over the whitewash.
The sides then shared a try apiece in the space of four minutes, with Josh Navidi picking up from the base of a ruck and barging over after Antoine Dupont had temporarily put France back in front with a fine score.
Wales took the lead for the first time 24 minutes in through Biggar's penalty, adding to his two successful conversions, only for Romain Ntamack to slot over seven minutes before the interval in an action-packed half.
A draw would have been enough for Wayne Pivac's men to seal top spot, though they pushed on early in the second period and added to their scoring through another Biggar penalty and a Josh Adams try.
Cardiff Blues wing Adams kicked the ball on and plunged over, the try allowed to stand after a lengthy TMO check, with France arguing the ball had been held up.
Ntamack split the sticks to reduce the arrears to seven points, but a yellow card for Mohamed Haouas and Biggar's subsequent penalty – after a Louis Rees-Zammit score was chalked off for grounding in-goal – left France with a huge mountain to climb.
Galthie's men were further frustrated when Julien Marchand and Dulin had tries ruled out, the latter proving a double blow as Willemse was dismissed for making contact with Alun Wyn Jones' eye at a ruck.
Yet there was to be a dramatic late twist as Faletau and Williams were sin-binned and France made the numerical advantage count, with Ollivon played in down the left for the game's sixth try and Dulin left alone to complete the famous comeback.
Poor discipline costs Wales
Willemse's red card was the third time a player has been sent off against Wales in this year's championship and left them in a very strong position.
It was Wales' own bad discipline that cost them in Paris, however, as Faletau was yellow carded for persistent infringements and Williams joined him in the sin bin for a deliberate knock-on.
France took full advantage by touching down twice in the final four minutes in what could prove to be a hugely costly defeat for Wales.
Captain fantastic denied at the death
Alun Wyn Jones was on the verge of becoming just the fourth player to win four Grand Slams, including one in three successive decades – something that has never been achieved before.
The Wales captain's 11 carries was the third most of any visiting player, while his 22 tackles made was the most of any player on the field.
Ultimately, though, he has to take a share of the blame for his side's inability to see out a Grand Slam-clinching triumph.
France now turn focus to that rescheduled clash with Scotland on home soil next Friday, with a bonus-point win required to pip Wales to the Six Nations title – their first since 2010.
Wales return to action later in the year with the autumn internationals, though a number of their players will be hopeful of representing the British and Irish Lions before then.