The Dutchwoman emerged from a four-rider breakaway sprint finish, victorious over Gracie Elvin (Orica-AIS), Trixi Worrack (Canyon/SRAM) and Anna van der Breggen (Rabo-Liv).
Blaak was satisfied with the team's second women's World Tour victory.
“I've been racing Drenthe since 2008, and I’m so happy I’m finally able to win here,” she said.
Tenderised by the first two cobbled sections and a strong RaboLiv pull towards the third section, the peloton broke into small pieces. Once off the third section with 60km to go, Van der Breggen attacked and Blaak, Elvin and Worrack applied the glue.
With four of the major teams represented in the break, it was left to Wiggle High5 to peg back the two minute deficit after missing the move of the day. The team worked hard, reducing the gap to as little as 15 seconds. A feat too much, Wiggle High5 called off the chase on the final shrug up the VAM-berg.
Blaak did not expect the break away to succeed.
“I didn’t expect we could ride away so early in the race. 60km from the finish, I led the peloton onto the last cobblestones, and just after that section, we were away with the four of us," she said.
Van der Breggen attacked in the final kilometre but was unable to stay away. Then Elvin opened the sprint.
“Gracie went very early and that surprised me a bit,” said Blaak. “I was able to jump in her wheel and finish the race with the win."
Missing out on the top step failed to quell Elvin's enthusiasm.
"It was a great day, a good day for everything to finally come together. I've been trying to put myself in the right place at the right time, but it hasn't quite paid off yet," she said.
"Today was good to show I've been doing all the right things. I hope to get a win soon. but I am still really happy with second place today," Elvin said.
Worrack said her ride today all came down to positioning.
"As soon as we came off the third section, Van der Breggen attacked. I was in about sixth position, and I saw her attack and Blaak then Elvin went with it, so I knew I needed to be there," she said.
Van der Breggen may not have won the race, but she now wears the WWT overall leader's jersey.
It's the fifth win this season for Boels-Dolmans but Blaak was careful not to classify the Boels-Dolmans team's dominance.
“It’s March...so much can happen during the season. We’ve only just begun. There are so many races still coming up.
"We try to make the best out of every race, but every day we start from zero," Blaak said.
And anything did happen, although the team's plan didn't change.