Dutch football clubs held a minute's silence and teams wore black arm bands before Sunday's professional matches in memory of a linesman who died following an incident during a youth competition last weekend.
Richard Nieuwenhuizen was attacked while officiating for the Buitenboys team in an under-17 match in Almere last Monday and the 41-year-old died the following day.
Four teenage Nieuw-Sloten Amsterdam players have been arrested.
After the mark of respect among the top flight clubs on Saturday, Ajax Amsterdam's Derk Boerrigter and Lasse Schone scored to earn a 2-0 home win over Groningen and cut the gap with leaders Twente Enschede to a point.