Both Geniez and Denz finished the stage 26:09 minutes down on Miguel Angel Lopez (Astana) in a large group that also includes teammates Julien Duval, Alexis Gougeard and Hugo Houle.
"After viewing the video footage that showed two of our riders intentionally holding onto the team car during the 20th stage (sic) on Sunday, September 3rd, the management of the AG2R La Mondiale team has decided to withdraw Alexandre Geniez and Nico Denz from the Vuelta a Espana," read the team statement.
"The AG2R La Mondiale team sincerely apologizes to the organizers and the public for the unsportsmanlike behavior of our riders, which is contrary to our values and our ethics."
The 2017 Vuelta is the first Grand Tour of Denz's career. The 23-year-old German was in 130th place overall at the conclusion of stage 15. For Geniez, the Grand Tour was the 11th of his career. It is also not the first time Geniez has been sanctioned following footage from a Grand Tour. Fan footage from the 2016 Giro d'Italia showed Geniez, then riding with FDJ, in an altercation with now teammate Hubert Dupont. Geniez was fined fined 200 Swiss Francs for 'improper conduct'.
Geniez is a two-time stage winner at the Vuelta and made his debut at the race in 2011 and issued a statement of apology via social media on the morning of stage 16.
"I made a mistake in hanging on to the car of the sports director during the final of the 15th stage of the Vuelta," wrote Geniez, who was the most combative on stage 3 of the Vuelta. "The team management of AG2R La Mondiale has decided to remove me from the Vuelta a Espana. This is difficult but I have to accept it
"I sincerely apologize to the organizers and the public, but also to my teammates for this behavior contrary to the values of my employer.
"I had a tough start to the season and today I just want to show on the bike that this incident does not reflect my vision of the sport."
In March at Paris-Nice, Romain Bardet was disqualified from the race for receiving illegal assistance from his team car.
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