Aberdeen defender Jack MacKenzie required stitches after he was hit in the head by a seat thrown by one of the club’s supporters.

A pitch invasion was sparked at Tannadiceon Saturday after Dundee United denied Aberdeen fourth place in the Scottish Premiership with a 2-1 win.

United supporters ran onto the pitch after the full-time whistle and some were seen goading the Aberdeen fans who were stood in the away section.

In a video shared on social media, various smaller objects were thrown at the United fans before a black seat was launched towards the pitch, hitting MacKenzie in the head.

The 24-year-old was left covered in blood due to the injuries around his left eye and required emergency medical treatment.

‘What’s happened is totally unacceptable. It is actually a bad injury but Jack is okay so let’s see how it feels after more minutes,’ said Aberdeen manager Jimmy Thelin .

“It is not acceptable, really really bad. I haven’t seen exactly what happened but our player got hurt, bad.

‘I think everyone understands that is not okay. He got treatment already and the medical team did really well.

‘There is the shock also when this happens. You are a football player in a football game and get hit like that.

‘We just take care of the player now and take it from there. He has had stitches.’

Meanwhile, United boss Jim Goodwin branded the incident ‘an absolute disgrace’.

‘I deliberately took myself off the pitch as quickly as I could because we’ve had previous with the Aberdeen supporters in the past,’ Goodwin told BBC Scotland.

‘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.’

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