Vlhova wins Flachau slalom to foil Shiffrin hunt for Vonn's record
Vlhova laid down the fastest opening run in 55.90 seconds, 0.17sec ahead of her American rival in second.
The Slovak made no mistake on the second run, in 56.05sec, for a combined winning total of 1min 51.95sec, 0.43sec ahead of Shiffrin, for her first victory of the season.
The pair were well ahead of the rest of the field under floodlights on the Griessenkar piste, with only Germany's Lena Duerr also finishing within one second of reigning Olympic champion Vlhova.
An 83rd World Cup victory would have seen Shiffrin surpass now-retired compatriot Lindsey Vonn as the female skier with most wins on the elite alpine skiing circuit.
To date, Shiffrin's 82 wins have been across all formats: slalom (51), giant slalom (17), super-G (5), downhill (3), city events (3), parallel slalom (2) and alpine combined (1).
Shiffrin picked up the first of those just over 10 years ago when she was only 17 and has taken just 233 starts to equal Vonn's record. Vonn, by contrast, started 395 races in her 13-year career -- she retired in 2019 at the age of 34.
Shiffrin is also just four wins shy of matching the overall record of 86 World Cup victories held by Swedish legend Ingemar Stenmark, who dominated the men's slalom and giant slalom disciplines for a decade from 1975 before retiring in 1989.
Next up for the women are back-to-back speed weekends, with downhill and super-G races in the Austrian resort of St Anton followed by those in Cortina d'Ampezzo, Italy.
There is a giant slalom in Kronplatz on January 24 before a giant slalom and slalom at the Czech resort of Spindleruv Mlyn on January 28-29, ahead of the World Ski Championships in Meribel and Courchevel.