Davy Klaassen suffered a head injury after being hit by an object thrown from the crowd during his team’s 2-1 win over Feyenoord on Wednesday.
The 30-year-old had put his side ahead in the second half but was struck by an object after he had tried to calm down an altercation between both sets of players.
Blood could be seen on the back of Klaassen’s head and the game was temporarily suspended for almost 30 minutes as both sets of players left the pitch at the Feyenoord’s De Kuip stadium.
Before the game restarted, Feyenoord’s assistant coach John de Wolf addressed the crowd via the public address system.
“Use your common sense,” he told fans, according to Reuters.