Vlhova was nearly nine-tenths off the pace in sixth after the first run before the Slovakian skier, who leads Gisin in both the overall and the slalom standings, improved to fourth with an attacking final run.
Vlhova had won all five slaloms since Shiffrin last won in Lienz, Austria, one year ago.
“I admire them since many years,” said Gisin, adding that her win “helps us to see that we got closer and it’s a fight again. It’s not just like we have two goddesses and we are just trying not to lose too much time. But we can fight for it. They improved the way we ski so have to be very grateful to them.”
Katharina Liensberger posted the fastest time in the final run and the Austrian trailed Gisin by 0.11 in second.
“It’s crazy. It’s just amazing,” Gisin said. “My first victory exactly eight years after my first race in the World Cup, exactly at the same place. I am just so happy.”
It was the first slalom win for the Swiss women’s team since Marlies Oester shared victory with Kristina Koznick of the United States at a race in Berchtesgaden, Germany, in January 2002.
The Swiss drought lasted for 162 slaloms.
“It’s good that Wendy (Holdener) and I won’t be asked about winning slaloms anymore,” said Gisin, referring to her Swiss teammate.
“I would like to win, for sure, and I was really pushing, but sometimes it works, sometimes it doesn’t,” she said. “The night is not so bad.”
The American was grateful with a podium result to end the most difficult year of her career, which included a 10-month break following the dead of her father, Jeff Shiffrin, in February.
“There is a lot of positive things to take from today. It’s a process going step by step,” said Shiffrin, who admitted she felt uncomfortable while waiting for her final run.
“I didn’t mange it very great but also, it wasn’t so bad. I was trying to bring good intensity, and sometimes it’s a little bit too much,” she said. “I try to remember how these things feel and it’s a good step in a good direction. Hopefully I can take that and keep moving in the right direction.”
Federica Brignone, who dethroned Shiffrin as overall champion last season, was 16th in the Italian’s weakest discipline.
Shiffrin’s American teammate Nina O’Brien scored a personal best in slalom, finishing ninth.
The floodlit slalom took place a day after strong winds had destroyed parts the finish area between two runs of a giant slalom as gusts blew away safety fencing and sponsor banners.
Workers rebuilt the setup at the bottom of the Zauberberg course early Tuesday.
The women’s World Cup continues with another slalom in Zagreb, Croatia, on Sunday.
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