Nielsen lands his first Tour win
Geraint Thomas retained the yellow jersey after Magnus Cort Nielsen won stage 15 of the Tour de France to Carcassonne.
Astana's Nielsen outsprinted Jon Izagirre of Bahrain-Merida and Bauke Mollema of Trek-Segafredo, the first three home from a 29-man breakaway which had been allowed to get away by the peloton.
The main contenders crossed the line more than 13 minutes later, with Thomas in the front group along with Sky team-mate Chris Froome, Team Sunweb's Tom Dumoulin, and Primoz Roglic of LottoNL-Jumbo to ensure there was no change in the general classification.
Ireland's Dan Martin finished 60th after crossing with the main group. Crucially, he remains tenth in the general classification.
Thomas continues to lead Froome by one minute and 39 seconds, with Dumoulin a further 11 seconds back. Roglic sits fourth, two minutes and 38 seconds down.
World champion Peter Sagan got into the breakaway, and he took third place in the day's intermediate sprint to all-but wrap up the points classification, receiving his 100th green jersey at the finish.
Sagan's Bora-Hansgrohe team-mate Rafal Majka attacked out of the breakaway on the climb of the Pic de Nore, crested some 41.5km from the finish, but was caught on the long descent towards Carcassonne as eight riders came together.
The final flat section towards town took the pack through fierce crosswinds, and that was the moment for Nielsen, Izagirre and Mollema to sneak off the front.
It is a second straight victory for Astana following Omar Fraile's win - also out of a breakaway - in Mende on Friday.
It is a first career Tour stage win for the 25-year-old Nielsen, whose previous season highlight was victory atop the Cow and Calf on stage two of the Tour de Yorkshire.