The stage brought the riders from Mende to Valence. Over 183 kilometres, the riders covered a rolling course with four ascents.
An early breakaway never got much advantage, so the stage ended in a bunch sprint. Greipel (Lotto-Soudal) was the fastest on the drag to the finish line and obtained his third victory in this Tour de France.
John Degenkolb (Giant-Alpecin) narrowly beat Kristoff Alexander (Katusha) for second. Chris Froome (Team Sky) maintained the yellow jersey, and Peter Sagan (Tinkoff-Saxo), who won the intermediate sprint and finished fourth on the stage, held on to the green jersey.
While the giant German has proven the fastest in the sprint, getting to the finish of the stage ready to attack didn't come easily.
“The first 18.5 kilometres were very important for me,” said Greipel, revealing that his biggest challenges was surviving the start of the day, rather than the finish.
“If I could survive in the beginning of the stage, I knew that I could sprint for the victory.
“The biggest task was to stay in the peloton during these tough first kilometres, I really suffered. Afterwards there was a plateau and then there was a downhill. The only obstacle left on the course was a climb of the second category.”
There were nine riders in the breakaway, among them Sagan and Lotto-Soudal rider Lars Bak. Their lead never went above the three minutes and at 30 kilometres before the finish they were caught by the peloton.
After that, the group prepared itself for a bunch sprint. Mark Cavendish (Etixx-QuickStep) didn’t participate in that sprint because he was stuck in a chasing group behind the peloton, where he had been since the beginning of the stage.
At the end, Stage 6 winner and three time cyclo-cross world champion Zdeněk Stybar (Etixx-QuickStep) tried to get away, but he was caught in the final kilometre. The expected sprint took place and Greipel was the strongest.
“I suffered the whole day and I had some problems with my knee,” Greipel, who managed the sprint victory without leadout men Greg Henderson and Marcel Sieberg, said.
“But with the finish line in sight, I can always give that extra push.
“I knew that in the final 250 metres, there was a headwind. My timing was just good enough, although Degenkolb and Kristoff came close.”
Greipel finished to the left of the bunch, but Australian team-mate Adam Hansen revealed to SBS afterwards the plan had been for him to target the right, in order mitigate the effects of the wind.
The Stage 15 win marks Greipel's ninth career victory at the Tour de France. In doing so, he clawed back 17 points in the green jerey classification by the end of the stage. Sagan maintained his lead over Greipel by 44 points.
“At first, we came to the Tour de France for one victory, the fact that we won three stages now is just a dream,” Greipel said.
“This sprint was the toughest of all sprint stages. The last chance will be on the Champs-Elysées, but first we’ll have to deal with the Alps. We will see what Paris brings.”