A man has been arrested and charged after Aberdeen’s Jack MacKenzie required stitches on a head injury after being hit with part of a chair thrown from the stand housing the club’s own fans.

MacKenzie, who was an unused sub, was on the pitch when both sets of fans spilled onto the pitch at the full-time whistle after Dundee United denied Aberdeen fourth place with a 2-1 win.

Aberdeen released a statement claiming the object came from the stand in which the club’s fans were housed.

The club said they were “dismayed and outraged”.

“Our player, Jack MacKenzie, has sustained a serious facial injury after being struck by a part of a chair that was thrown towards the pitch,” the club said.

“We await further information, but what we know for sure, the chair was thrown from the stand in which the Aberdeen supporters were being housed.

“As such, we are calling on all fans who may have witnessed this event to contact the club to provide any information that may assist us in our investigations and wider discussions with the relevant authorities.

“When the perpetrator is identified, we will take the strongest possible action available to us.”

Police Scotland have now confirmed a 31-year-old man has been arrested and charged in connection. He is expected to appear at Dundee Sheriff Court on Wednesday.

Speaking to BBC Scotland, Dundee United boss Jim Goodwin labelled the incident “a disgrace” with Aberdeen boss Jimmy Thelin telling the club’s in-house media channel that the full-back had been “badly injured”.

Goodwin said: “I deliberately took myself off the pitch as quickly as I could because we’ve had previous with the Aberdeen supporters in the past.

“I’m really disappointed to hear young Jack has been hit by an object thrown by his own supporters. He’s inside having stitches now, it’s an absolute disgrace.

“It’s probably taken something as serious as this to happen for the authorities to finally step in and do something about it to identify these idiots who let down a really good club.”

An SPFL spokesperson said: “It’s enormously disappointing and frustrating that one of the most exciting games in the season has been marred by such moronic behaviour.

“We await the match delegate report but will work closely with both clubs and Police Scotland to help identify the perpetrator and fully expect that appropriately severe footballing and judicial sanctions will be imposed.”

Police Scotland Match Commander, Superintendent Ray Birnie, said: “This was a mindless act which has seriously injured the player resulting in him needing medical treatment.

“This type of behaviour will not be tolerated and I’d appeal to all fans to help us trace the person responsible.

“If you were in the Fair Play stand and witnessed what happened, please do the right thing and come forward. I’d also urge anyone who has mobile phone footage to review it and bring anything of importance to our attention.”