The Lotto-Soudal rider came from behind to finish ahead of an accelerating Peter Sagan (Tinkoff-Saxo) and fading Mark Cavendish (Etixx-QuickStep).
The general classification remained unchanged, with Etixx-QuickStep’s Tony Martin the first rider in this Tour to hold on to the yellow jersey for more than one day. He continues to lead Chris Froome (Sky) and Tejay van Garderen (BMC).
The 189.5km stage from Arras Communauté Urbaine to Amiens Métropole featured numerous directional changes with the peloton riding into a block headwind as they came to the finale. This perhaps helped the larger, more powerful men like Greipel.
Timing proved essential in Greipel's win, who said he had to improvise to come out on top of the other fast men.
"It was an interesting sprint because none of the top sprinters had any of their lead-out men to lead the sprint for them in the final 300 metres," said Greipel. "You had to improvise a little bit. I looked for an opening and saw there was one on the left. I was a bit far off at the 300 metres but I was lucky to still have the strength to pull it off."
Etixx-QuickStep's Mark Cavendish was downbeat after being beaten to the punch by Greipel (and Sagan) for the second time this week.
“I think instead of the news being that I'm beaten again, maybe it should be that Greipel has won. He's a phenomenal sprinter, he's in the green jersey and that's the second stage he won this year.” he told reporters gathered outside the team bus after the stage.
"It was a bit chaotic. I went around Sagan, then I kicked. I saw Démare kick and on his right, Kristoff. I went by Démare and then drag-stripped Kristoff, but then Greipel and Sagan just came past me in the end. I didn't feel great in the sprint, but nobody felt good today. I was going ok, they just went fastest.”
The stage was designed to pay homage to soldiers who had died on the battlefields of northern France during World War I and the peloton rode through the Somme battlefield and past a number of war cemeteries.
Pierre-Luc Perichon (Bretagne Séché Environnement) was the first to attack, making a solo break right from the gun. However, he was never let far off the leash and his TV time ended after 90km off the front.
Strong winds troubled the peloton repeatedly, causing splits and spitting out the injured or weak. Even so, the main field regrouped after each instance, with a weary peloton content to see the stage end in a sprint. A late crash towards the rear of the peloton with 25km to go temporarily delayed a number of backmarkers, but the majority of those affected shrugged off the falls to regroup once again.
Two riders who did abandon during the stage were Cofidis sprinter Nacer Bouhanni and New Zealander Jack Bauer (Cannondale-Garmin). Bouhanni, who crashed just 10 days ago in the finale of the French Championships was taken to hospital by ambulance.