Sam Bird completed his strongest Euroseries weekend yet in sixth place, the Brit tailing Vernay and Maki all the way to the flag but being unable to find a way past on the twisty Dutch circuit.
Just outside the points, James Jakes finished seventh to bring an end to another poor weekend for the ART driver, while team-mate Jon Lancaster ended his race in the gravel trap after a clash with Henkie Waldschmidt.
In the championship fight, Mortara, remarkably, holds onto his lead by a healthy nine points despite failing to score for the first time this season. However, with closest rival Hulkenberg also being unable to get record any points, the Italian remains safe at the top of the standings.
His nearest challenge comes from Maki now, while van der Zande's victory lifts him up to third, just ahead of Nico Hulkenberg and Christian Vietoris, the latter of which unable to score any points himself this weekend.