Lotto Soudal were taking turns pacing on the front with Alpecin-Deceuninck and TotalEnergies as the race moved into the last 20 kilometres, trying to catch the three man break of Fred Wright (Bahrain Victorious), Jasper Stuyven (Trek-Segafredo) and Alexis Gougeard (B&B Hotels) who held only a slender advantage.
But the gap was still at 10 seconds as they reached the final two kilometres, delaying lead-out trains for sprinters like Ewan getting in position as the stubborn break just couldn't be caught on a stage that many had thought a certainty to end in a bunch sprint.
Instead, Christophe Laporte (Jumbo-Visma) bridged across to the break and attacked in the last 500 metres to win the stage solo, Ewan competing for second in the chase behind only to finish 10th.
It was yet another disappointing moment in a Tour de France which has been filled with negatives for the Australian, closer to withdrawing than sprinting for victories after crashing multiple times and struggling against the time cut in the mountains.
"I'm super disappointed with today," A dejected Ewan told SBS following the stage.
"It was a finish that really suited me, slight uphill - I really wanted to win today but the stage is gone and it's another disappointment.
"To be honest, the big stuff-up of the day was that we brought the break back halfway through the stage, I don't know why we did that.
"We knew it was a strong break but I don't know what's worse, a break that's been out there for 180 kilometres accelerating at the end, or fresh guys going with 30 kilometres to go.
"We had to use way too many guys at the end to bring back that small breakaway. Then at the end in the sprint, no-one really had teammates left and we just all sat up and the stage was gone."
Just one opportunity remains for Ewan, the stage 21 finish on the Champs-Elysees which he didn't get the chance to compete in last year after leaving the race early with a broken collarbone.
"If I could win any stage of the Tour de France it would probably be the one in Paris, so that one's still left. When there's still a chance there's still hope to win.
"I think I can take the positive that I felt good, and as I get better through the Tour I think it's going to be hopefully a good stage for me."
Before that though, Ewan faces another battle with the time cut in tomorrow's individual time trial where you can't take it easy by any means, even after a brutal 19 days of racing.
"I just have to get through the time trial tomorrow," Ewan said.
"It's never easy and you still have to push quite hard to make the time limit."
The Tour de France continues with Stage 20, a 40.7-kilometre time trial into Rocamadour. Watch from 8.55pm AEST on the SBS SKODA Tour Tracker, with the SBS and SBS On Demand broadcast starting from 9.30pm AEST.
