Utrecht won only their second game of the season at home to newly-promoted Go Ahead Eagles.
Go Ahead wasted several good chances in the first half, but were made to pay for their profligacy when Sébastien Haller had a shot blocked, and Giovanni Troupée stuck a foot out to loop the ball over the rooted goalkeeper Zwarthoed.
Rico Strider and Richairo Zivkovic added further goals in the second half to give the score an arguably unfair reflection.
The win sends Utrecht up to twelth position whilst Go Ahead remain fifteenth.