Heerenveen boss Robin van Persie was left exasperated after match officials mistakenly allowed Fortuna Sittard to field 12 players against his side on Saturday.

The incident took place in the 88th minute with Heerenveen 2-1 up, when Fortuna made a double-substitution that saw Ryan Fosso and Jasper Dahlhaus come off for Darijo Grujcic and Owen Johnson. However, Dahlhaus didn't step off the pitch and played for nearly a minute.

Van Persie noticed the man advantage to Fortuna and protested on the sidelines before Dahlhaus eventually came off. A minute later, Fortuna equalised through a corner to snatch three points away from Heerenveen.

"I find what preceded that goal very special," Van Persie said post-match. "Fortuna Sittard had 12 men on the field for a minute before that throw-in. Apparently that is allowed and possible. You can't imagine that? That it is simply allowed.

"Normally I never talk to referees and always let them do their job, but it can't be that they play with twelve men. That's unthinkable. So I asked the fourth official: 'Shouldn't you do something about that?'"

When asked what he'd like to see done, Van Persie said: "For example, reverse that goal. You can't play with twelve men against eleven. I really can't understand that. I think this is really scandalous."

The former Manchester United and Arsenal forward took over at Heerenveen in May last year. His side are 10th in the Eredivisie after 21 games.

Information from ESPN Netherlands contributed to this report.