There or not so much thereabouts in the bunch sprints with Marcel Kittel (QuickStep Floors) and Arnaud Demare the rest of the Tour, the Dutchman left nothing to chance, letting rip early with around 350 metres to go.
For a brief moment, Greipel looked like he might catch Groenewegen but it was a comfortable win for the 24-year-old LottoNL-Jumbo rider in the end.
"We're only five riders in the team but it was enough today," Groenewegen said. "They put me in a good position, on the wheel of Alexander Kristoff and then I rushed to the finish line.
"This is my first stage win at the Tour. When I was young, I was looking at the Champs-Elysées stage on TV. Now I'm the winner here, it's wonderful.”
“This is an amazing place for the sprinters. To win on the Champs-Elysées makes it a perfect day."
[tdf widget="stagewinners" stage="21"]
After the champagne was sipped and the jersey and other photos were taken, Daryl Impey (Orica-Scott) attacked as the Sky-led peloton hit the Champs-Élysées. Cruelly taking away an opportunity for Thomas Voeckler to lead the peloton on to the iconic circuit, as is the custom for retiring riders, Impey was soon joined by Guillaume van Keirsbulck (Wanty) who would soon falter.
Attacks aplenty followed until Imañol Erviti (Movistar), Miki Schär (BMC), Alexey Lutsenko (Astana), Julien Vermote (Quick-Step Floors), Marcus Burghardt (Bora-Hansgrohe), Nils Politt (Katusha-Alpecin), Sylvain Chavanel (Direct Energie), Dion Smith (Wanty-Groupe Gobert) and Impey enjoyed a 20 seconds lead with 45 kilometres to go.
With two laps to go, Tony Martin (Katusha) attacked from the pack in a failed bid to bridge to the leaders who were caught with 10 kilometres left to race.
As the sprint trains of Lotto-Soudal, LottoNL-Jumbo and Katusha began to saddle up for the sprint, they easily reined in a late attack from Zdenek Stybar (Quick-Step Floors) with two kilometres to go.
[tdf widget="tourleaders" stage="21"]