There is no doubting Paralympic swimmer Aurèlie Rivard's proficiency.

The Saint-Jean-sur-Richelieu, Que., native is a 10-time Paralympic medallist, half of which are gold. She's won another 19 medals at world championships.

Rivard currently holds four world records in her S10 classification, a category reserved for the least impaired freestyle, backstroke and butterfly swimmers.

She's already reached more world-championship podiums than any other Canadian woman, and at 28, she's a legitimate threat to surpass Chantal Petitclerc and Michael Edgson, with 21 medals apiece, as the most decorated Canadian summer Paralympian ever.

Rivard's coach Marc-André Pelletier put it succinctly: "she's f---ing good."

And yet there's one race, one discipline in particular, that has become a thorn in Rivard's side.

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Canada's Aurelie Rivard golden at the Para swimming worlds

Aurelie Rivard of St-Jean-sur-Richelieu, QC., claimed gold in the 100 metre freestyle S10 final at the world para swimming championships in Madeira, Portugal.

In 2012 at her debut Paralympics, Rivard won silver in the 400 freestyle. In 2016, she bumped that up to gold. In 2021, she broke her own world record to repeat as champion.

And then something funny happened at the 2022 world championships in Portugal.

Rivard led at the 50-metre mark. She led at the 100-metre mark, and the 150. Throughout, Hungary's Bianka Pap emerged as the Canadian's lone competitor, touching the halfway point just one-tenth of a second behind Rivard.

But Rivard looked strong. She even extended her lead slightly at the 250-metre mark.

And then she stopped. Pap swam on, gaining about a quarter-length advantage as Rivard held on to the wall like a kid in swimming class.

WATCH | Rivard stops swimming mid-race at 2022 worlds:

Aurelie Rivard pulls up during 400m freestyle at 2022 world championships

Canadian Paralympian forced to stop racing during event in Portugal.

Finally, Rivard tried to go again. She dove back underwater, came up, took one stroke, then stopped again, paused a moment to lean on the lane divider, then exited the pool.

The play-by-play commentator theorized that Rivard may have taken on water. Maybe it was just a one-off.

But one year later, at worlds in England, it happened again. This time, though, there was no water to blame.

Rivard qualified for the final, then suddenly pulled out before the race began.

Paris 2024, then, promises to provide a new kind of challenge for Canada's biggest Para swimming star. While there will always be the question of how many, Rivard – at least as it relates to the 400 free – will simply have to answer 'how.'

How will she feel in the green room? How can she slay that elephant in her head and clear her mind just to get in the water? And how can she last the gruelling 400 metres – and come out with a medal?

In response to those questions, Rivard had one more.

"How much time do you have?" she responded when the topic of the 400 free came up. "It's been complicated to say the least. People first knew me through the 400. That was my first medal in London. It was the first goal I ever set for myself. It was the first time that I was like, 'Oh my God, maybe I can win a gold medal in an event.'" 

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"I have put so much effort and time into this race over the past decade. And I feel like I pushed it probably not to the max, but so far that the room for improvement is very little, very small. And because I've won it so many times and it was never easy, I have high standards for it."

The women's S10 400 freestyle takes place on Sept. 5 at Paris La Defense Arena, with heats in the morning and the final at night.

Perhaps, when Pap was providing a legitimate threat to her crown in 2022, Rivard's ego interrupted — anything worse than gold was unacceptable.

"I can't really just dive in and do a full 400 just for fun. It never happens. I have too many points of reference, I've done it too many times. And it's a hard race, [physically] it's a really tough race. And as soon as I feel like something's off, it's really hard for me," she said.

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Quebec's Aurelie Rivard wins Para worlds 50m freestyle S10 gold for a third time

Aurelie Rivard of Saint-Jean-sur-Richelieu, Que., won the women's 50-metre freestyle S10 event at the 2023 Para Swimming World Championships in Manchester, England. Rivard also won this event at the 2015 and 2022 Para worlds, and the 2016 Paralympics.

To help soothe her mental battle, Rivard said she began working with a sports psychologist following the 2023 no-show. She now admits that jumping back into the pool at a major event like worlds so soon after 2022 was a mistake, having not fully recovered from her shocking stoppage a year prior.

Not that she would consider skipping the Paralympics, but Rivard has taken a different approach, attempting to rebuild her confidence slowly but steadily.

Now, she's been back at it full-time for 18 months. She trains in Quebec City with her coach, Pelletier, and a group that includes two-time Paralympic medallist Nicolas-Guy Turbide and two-time able-bodied world medallist Katerine Savard.

Pelletier's training group benefits her by providing the likes of Savard who can truly test Rivard in the pool more than some of her fellow Para competitors.

"I have to put her in a situation that's close to the same she's going to feel in competition. That's the point of racing against girls of her level — you know, racing, racing, racing," he said.

Due to a knee injury, Rivard dropped the 200 individual medley for Paris, leaving her with just four individual races: the 100 backstroke, and the 50, 100 and 400 free.

Pelletier said the program makes training somewhat easier, since freestyle is less complicated than, say, breaststroke.

And since Rivard is already working with others on the mental side, Pelletier's focus is firmly on the pool.

"For me here, it's about knowing it's there, but not acting like it was an issue," he said. "It's small victories every day. Always a challenge just being sure that if the situation happens, you have tools in your box to deal with it."

From a physical standpoint, Pelletier doesn't foresee much competition for Rivard.

"If she decides she's gonna win, she will win. But she needs to be confident. She needs to be relaxed," he said.

Rivard knows it, too.

"It's me. I am my biggest competitor. The person that scares me the most in that race is me. I want to beat me. I don't really care about the other girls."