Go Ahead Eagles fans attacked De Graafschap players after a Dutch second division match on Sunday.
Television footage showed Go Ahead supporters running on to the pitch at the end of the game, which their team lost 4-0 at home, kicking and punching De Graafschap players before stewards stepped in.
Go Ahead said they were "deeply ashamed" of their fans' behaviour which they condemned.
"The club makes every effort to take appropriate measures against those responsible," Go Ahead said in a statement on their website.
The start of the game had been delayed by several minutes after spectators threw fireworks on to the pitch.
The police made seven arrests, Fox Sports Netherlands reported.