The fastest racer to that point — with the No. 13 bib — Cook ended up fifth to match Lindsey Vonn for the best result by the U.S. women's speed team this season.
With Vonn out injured, this race marked a big breakthrough two weeks before the opening ceremony for the Sochi Olympics for Cook and a team that has struggled all season.
Cook was joined by teammates Julia Mancuso in ninth, rookie Jacqueline Wiles in 15th for her first World Cup points and Laurenne Ross in 17th for her best result of the season.
"Awesome," U.S. women's head coach Alex Hoedlmoser said. "As I've always said, 'They're way better than they have been skiing.' And now it shows slowly in the results, too. ... We're heading in the right direction.
"They've been skiing well in training and now they're starting to believe in themselves, too," added Hoedlmoser, who will name his team for Sochi on Sunday.
The race was won by overall World Cup leader Maria Hoefl-Riesch on a course that was shortened slightly due to overnight snowfall.
The revised start put skiers directly into the course's best-known section, the Tofane Schuss — a long straightaway between two high rock outcroppings.
"I generally do OK when there are straight shots out of the gate like that," Cook said. "So that was a little confidence booster to kick out of the gate, get on my skis and not have to do too much and then get into it. And then I just tried to not ski a perfect line but ski perfect body position and really attacking. And it seems to have been fast."
Cook missed the podium by a mere 0.03 seconds, showing the same speed that earned her second-place finishes in consecutive downhills last season in Lake Louise, Alberta.
Cook also won a downhill training session earlier this season in Beaver Creek, Colo., but couldn't maintain her speed.
"I was a little nervous at the start, because I feel like I've been prepared all year and then on race day things just haven't come together," said Cook, who at 29 is the same age as Vonn and Mancuso. "I really wanted to make it come together today."
Mancuso won the only training session Wednesday and wasn't pleased that the course was shortened.
"There's a lot less room for error — you really can't make any mistakes. That's kind of what happened to me today," she said. "I just was going for it and that's what happens, you make mistakes. But the speed is definitely there.
"In ski racing it's kind of like there's nothing to lose," Mancuso added. "You can't fail unless you try really hard. So we're just getting our speed back."
Mancuso finished seventh in Thursday's super-G and now has two consecutive top-10 results after failing to break into the top 10 previously this season.
"Now it's just a matter of having that run where everything comes together, and I'm feeling positive it will come soon," Mancuso said.
Last season, every member of the speed team reached the podium.
"We're getting close," Cook said. "Best-ever seasons are hard to repeat, especially when we're down two of our best teammates. Lindsey obviously takes a lot of pressure off the rest of us and Alice (McKennis, who is also injured) is a support system that we all rely on."
Another downhill is scheduled for Saturday, followed by a super-G on Sunday to round out four consecutive days of racing
The 21-year-old Wiles is enjoying the repetition, too. As a rookie, all of the courses in Europe are new to her.
"So there's a lot of nerves," said Wiles, who was 12th in training. "That's been quite an experience. But I think I'm doing well with it, and I'm trying to keep my nerves under control and do the best that I can."
Usually, racers take a few years to study courses before they can really attack. Not Wiles.
"That's pretty amazing," Hoedlmoser said. "Because it's not an easy downhill."
Already two-time U.S. downhill champion, Wiles' chances of being selected to the Olympic team just got a big boost.
When Vonn announced this month that she would not race in Sochi, she noted that it would open up a spot for one of her teammates.
That could be Wiles.
"Yeah, that's exciting," Wiles said. "We'll see. I'll have to keep pushing hard."
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