Sheppard, who rides for the Swiss Wheeler IXS team, pushed hard from the start to dominate the race, winning by nearly two minutes on arguably the toughest track on the World Cup circuit at Mont Sainte Anne near Quebec City.
It presented an early birthday gift for the Rotorua-based Wellington rider, who turns 22 tomorrow.
“It means everything,” Sheppard said. “Wow, my first World Cup win is pretty awesome but I was so, so exhausted I couldn’t even open my bottle of bubbles on the podium.”
It was a double podium day for the New Zealanders with Rotorua student Amber Johnston finishing third in the junior women’s race.
Sheppard said she wanted to stamp her dominance on the race.
“The rain came through just before we started which made the course super slippery. It tried to find a rhythm and ride smart or what wasn’t possible to ride, get off and run. I got out in front and rode my own race.”
She beat off a talented field including World Cup leader Yana Belomoyna (UKR), a two-time winner this year, her teammate Jolanda Neff (SUI) who won in the Czech Republic and Australian Rebecca, who recorded her third podium of the season.
“Definitely it was a tough field as all the World Cup races are. But I always love coming here. It's a really tough track and I think everyone loves it to be honest. It’s got everything. It is so physical. You can’t let up or you'll crash.”
Sheppard believes the win will prove a turning point for her.
“To come here to do it on my favourite track is great. It shows I’ve been training really well. We’ve got a good programme going into Worlds and everything is coming together nicely. Basing myself in Europe and with the Wheeler ISC team support, I'm really happy with how things are going.
“Once I got on the podium at the last round then I started to believe in myself more, and now I know I can go out there and win. It definitely gives me a lot more confidence for the rest of the season leading into Austria (World Championships in September).”
The victory moves Sheppard to third overall on the World Cup standings with two rounds remaining.
Johnston, the Oceania under-19 champion, grabbed third place in the junior women’s race after holding off Canada’s Rachel Pageau in a sprint finish for third place. She finished only 2:39 from winner Frederique Tredel (CAN) in her first World Cup start.
Teammate Samantha Hope (Dunedin) finished eighth.
Earlier Brad Hudson (Christchurch) and Tom Bradshaw (Palmerston North) finished mid-pack in the men’s under-23 race.
Europe’s best crossed the Atlantic to take on North America’s top riders with overnight rain making the brutal cross-country course treacherous.
Manawatu’s Matthew Waghorn made a strong start and by lap three had forced his way through the pack but he crashed on one of the slippery descents and was also forced to make a tyre change, before his replacement tyre got slashed on a sharp rock on the following lap to end his chances.
Hudson was caught in a bunch start but slowly worked his way through the field to be leading Kiwi in 34th while Bradshaw made a fast start before fading on the tough climbs to finish 37th.
“It is definitely good to have a World Cup start under my belt, I will be doing things a little differently next weekend,” Hudson said. “The experience is invaluable no matter what happens, but I am really looking forward to a better result next weekend."
Waghorn said there were plenty of positives in his race.
“I made an excellent start, which was good to see the training I have been working on in New Zealand paid off, but unfortunately the rock always wins and this course has lots of sharp rocks."
Bradshaw’s introduction to World Cup racing proved an invaluable experience.
“It was a good eye-opener for me about where my riding is at. I knew it would be hard coming over from the New Zealand winter and racing all the Europeans, but that is why we are here, because it is hard."
Tomorrow Cooper races in the junior cross-country, with six New Zealand riders qualifying for the final of the downhill including Brook MacDonald, Justin Leov, Sam Blenkinsop, George Brannigan, Cameron Cole and Kieran Bennett.
Under 23 women: Samara Sheppard (NZL, Wheeler IXS) 1:22.18, 1; Yana Belomoyna (UKR) 1:34.29, 2; Rebecca Henderson (AUS) 1:35.48, 3.
Under 23 men: Michiel Van der Heijden (NED) 1:26.57, 1; Gerhard Kerschbaumer (ITA) 1:27.31, 2; Markus Schulte-Leunzum (GER) 1:28.46, 3. Also New Zealanders: Brad Hudson (Christchurch) 1:39.19, 34; Tom Bradshaw 1:42.47, 37; Mathew Waghorn dnf.
Junior women: Frederique Trudel (CAN) 1:18.30, 1; Dina Hordiyuk (UKR) 1:19.32, 2; Amber Johnston (NZL) 1:21.09, 3. Also: Samantha Hope (NZL) 1:26.46, 8.
Elite women: Catharine Pendrel (CAN) 1:41.40, 1; Georgia Gould (USA) 1:42.03, 2; Marie-Helene Premont (CAN) 1:43.31, 3.
Elite men: Nino Schurter (SUI) 1:41.24, 1; Jose Hermida Ramos (ESP) 1:41.24, 2; Jaroslav Kulhavy (CZE) 1:43.13, 3.