Paula Blasi pulled off a stunning upset on Sunday, winning the women's Amstel Gold Race in Valkenburg after a bold solo attack.

The Spanish rider launched her decisive move 22 kilometers from the finish on the penultimate ascent of the Cauberg and never looked back.

Blasi built a lead of nearly a minute with 10 kilometers remaining before holding off the chasers to take the biggest victory of her career.

Kasia Niewiadoma and Demi Vollering, both former Tour de France winners, were slow to respond and finished around 30 seconds behind in second and third.

"It's incredible. I wasn't even supposed to ride this race," Blasi said.

"I got the call at the last minute to replace injured teammates."

The 23-year-old briefly rode with Nienke Vinke before pushing on alone and committing fully to her attack.

"I was yo-yoing a lot during the race, sometimes dropped in a very nervous bunch," she said.

"So I chose to go on the attack to get out of this slightly crazy peloton. And it paid off."

Paula Blasi Announces Herself As Rising Star

The former triathlete and time trial specialist secured her fifth professional win and by far the most significant of her career.

Blasi has already shown her potential with a European title and a bronze medal at the U23 World Championships.

The Ardennes Classics continue on Wednesday with La Flèche Wallonne.