Guarnier enjoyed a comfortable 34 second advantage over team-mate and fellow American Evelyn Stevens, while the 2015 winner Anna Van Der Breggen of the Netherlands began the day 1min 53sec back in third.

The gap to Guarnier’s closest rivals allowed the Boels Dolmans team to allow a breakaway group of nine riders to move clear in the early stages of the 105 kilometre course in Verbania.

De Jong was among the riders in the move, along with Australia’s Lauren Kitchen, the Netherlands’ Riejanne Markus and Japan’s Mauyko Hagiwara, a stage winner in last year’s race.

The group built up a strong advantage over the peloton heading into the final climb of the day, with De Jong opting to attack her breakaway companions upon reaching the summit.

She was able to grow her advantage in the closing kilometres and eventually claimed stage 10 victory by finishing in a time of 2hr, 44min and 24sec.

Markus and Italy’s Maria Giulia Confalonieri completed the top three after leading the remnants of the break over the line, 1:05 down.

The peloton eventually came in 52 seconds adrift, with Guarnier having preserved her advantage over both Stevens and Van Der Breggen.

Guarnier became only the second American to triumph in the stage race, which is part of the International Cycling Union (UCI) Women’s WorldTour, with Mara Abbott having won in both 2010 and 2013.

The victory also continued Guarnier’s fine season, with the American having won both the Philadelphia Cycling Classic and the Tour of California to lead the WorldTour standings.