After the two sides got into heated arguments following Luciano Valente's red card in injury time, players of FC Groningen and Ajax got into a scuffle after the full-time whistle had blown. FC Groningen goalkeeper Etienne Vaessen seemed the centre of attention after getting into an argument with several Ajax figures.
Footage of the scuffle soon went viral, and the KNVB announced on Thursday that it had started a preliminary investigation into Etienne Vaessen's role in the scuffle.
"The prosecution has observed on TV footage that Vaessen repeatedly aggressively seeks confrontation with Ajax players and/or staff members, and he punches a player or staff member of Ajax who is sitting on the ground," said a KNVB spokesman in a statement.
Suspension
The KNVB announced earlier on Thursday that midfielder Valente received a two-game suspension after receiving a red card against Ajax. The Dutch youth international lunged into a challenge with Jordan Henderson with a two-footed tackle in the 93rd minute, which cost the Italian-Dutch midfielder a sending-off.
FC Groningen have appealed the decision.