The Croats are bottom on no points and can now only fight for third spot and a Europa League place with two games left.
A superb back-heel pass by Christian Eriksen played in Van der Wiel, who first searched for a team-mate before deciding to shoot and score the first on 20 minutes.
Ajax are second in Group D with seven points after four matches, three ahead of next opponents Olympique Lyon. A scoring draw in France on November 22 would send Frank de Boer's side through.
"They surprised us a bit with their tactical plan but we regained control and kept them under pressure," De Boer told reporters.
The 4-0 scoreline also helped Ajax's goal difference compared to Lyon if the head-to-head between the sides does not come into play.
"We know that a score draw will do in our next match at Lyon but we are not a team that just can lean back on the counter attack, so we will also try to play our own game in Lyon but with cleverness," the coach added.
