But on a happier note, Greg Van Avermaet extended his overall race lead to 43 seconds over Team Sky's Geraint Thomas, while the Belgian is also expected to confirm that he'll stay with the team in 2019 as part of a team-saving merger with CCC Sprandi secured by manager Jim Ochowicz.
Van Avermaet was disappointed not to win the stage while wearing the iconic yellow jersey after being beaten by Trek-Segafredo's John Degenkolb, but accepted defeat and vowed to fight on despite the loss of Porte.
"I thought I was going to win. I believed in my sprint," the Belgian rider said, his usually controlled voice an octave sadder in disappointment.
"I think it would have been a really nice picture, winning in this jersey. That was a really big goal. But sometimes you win, sometimes you lose, and that's it. Maybe I started a little too late – maybe I should have attacked by myself first, but after any race you always look for an explanation about how you could win. For me, it's a big disappointment."
Van Avermaet was gutted to hear the news that Porte had crashed early on in the stage.
"It's pretty bad news. We came with Richie as our GC rider, and it was always a goal to get him onto the podium in Paris," he said, putting the team's loss in clear context.
"The sad thing is that it's now two years in a row that we've lost him," continued Van Avermaet. "It's hard for the team, because we built a team around him. In the first week, I've had my freedom, but in the second and third week I wanted to work for him, but now he's not here anymore, so it's going to be pretty hard to show ourselves on the mountain stages.
"It happening two years in a row also makes a big difference, I think. You can lose your GC guy one year, but not two years in a row. He's 33 now, so it's not great for him. It won't be easy for him to get back into the right mindset.
"The good thing is, though, that his crash was not as bad as the crash last year, so he'll recover faster. Hopefully he'll be back on his bike quickly and will maybe do the Vuelta or something."
Savouring the good results, not the bad news
Van Avermaet hinted that he might try to defend the yellow jersey for one extra day on Tuesday, when the Tour de France heads into the Alps for a tough stage between Annecy and Le Grand Bornand. The 33-year-old knows that the stage is packed with mountains, and even a dirt section on the Montée du Plateau des Glières. But he says that he's more suited to stage 13 to Valence on Friday or Saturday's 14th stage to Mende.
"I've improved on the climbs, but not that much," he warned. "I think for us it's going to be super-hard, too, like we saw last year when we lost Richie. It was really hard to regroup for a good second and third week, but we'll hope that Tejay [van Garderen] steps up and is able to do something in the mountains."
BMC directeur sportif Fabio Baldato also tried to rally his troops after a hard day on the pavé.
"Once again, we'll try to keep looking forward to the end of the Tour, and try to take some stages if it's possible, as the GC and the podium is gone," he said.
Van Garderen preferred to look back and savour BMC Racing's success in the opening nine days, rather than trying to look to the future.
"I'm really happy about this first week," the American said. "We should all be happy.
"We took a stage win with the team in Cholet," continued van Garderen, "and we've had six days with Greg in the yellow jersey, so that's already something. The Tour is going to be an open race for us now; maybe we'll have more freedom. Maybe I'll try to go in the break and so defend the yellow jersey on Tuesday. Our Tour is far from over."