Alena Amialiusik (SRAM/Canyon) and Leah Kirchmann (Liv-Plantur) also came home with the trio.
The lead group was followed by a bunch of stragglers that remained from the lead group of 14.
The Polish national road champion Niewiadoma was chuffed with the win because of the caliber of her "domestique".
"I tried to get away with Anna van der Breggen (earlier), but could not," the 21-year-old said.
"When Anna told me I had to finish it and she would work for me; if the Olympic champion says that, you know what to do. Luckily I could finish it." Niewiadoma said.
With her sprint to third, Blaak is now the new race leader.
“It didn’t feel like a sprint,” said Blaak. “It was go as fast as you can. They went from the bottom already full, so that’s not a sprint anymore. That’s who has the legs.”
“I was cracked,” sadi Blaak. “That last lap was so, so hard.”
As it happened
Several riders attempted attacks in the opening 30 kilometres but failed. After the bunch broke in two on the Snijdersberg, Roxanne Knetemann (Rabobank Liv) and Esra Tromp (Parkhotel Valkenburg) took their chances and quickly built a 40 second lead after 35kms raced.
The passage at the Snijdersberg after 30 km. @ellenvdijk @boelsdolmansct in front. #BRLT16 pic.twitter.com/bQplyygGbw — Holland Ladies Tour (@ladiestour) September 1, 2016
Niewiadoma's team mate worked with Tromp to soften up the bunch for more than sixty kilometres.
After 75 kilometres raced, the pair had built a maximum lead of two minutes and 35 seconds. But the speed back in the bunch soon increased resulting in a bunch split into three and a dwindling one minute and five second lead.
The bunch in 3 parts. @L_ArmiTstead @boelsdolmansct is pacing the bunch. #BRLT16 pic.twitter.com/4hgPLQ3rZZ — Holland Ladies Tour (@ladiestour) September 1, 2016
The pair were caught with 25 kilometres to go, a good day's work complete.
The front group of 15 riders contained the likes of Australia's Amanda Spratt and Gracie Elvin (Orica-AIS), Wiggle High5's Amy Pieters and Audrey Cordon, Boels Dolmans riders Chantal Blaak and Ellen van Dijk and Rio Olympic champion Anna Van de Breggen working alongside Niewiadoma.
Blaak said the final lap comprised several attacks.
“I attacked but then I saw Anna [van der Breggen] and Alena so I stopped,” said Blaak. “I didn’t work. That’s when it came back together.”
Eight kilometres from the finish, a truce was called as the leaders prepared themselves for the tough finale.
Elvin fell out the back and the front 14 riders remained together until Niewiadoma's sprint at the end.
