A SOUTHAMPTON man has been arrested on suspicion of causing grievous bodily harm following an incident at St Mary's Stadium last night.

Police say the 28-year-old was detained after an older man suffered a serious head injury following the end of the game, which saw Saints crash out of the FA Cup.

Southampton were beaten 2-1 by League Two side Grimsby Town.

Shortly after the match finished, fans took to social media to voice their dismay at a "horrific" incident that occurred as people were leaving the stadium.

One witness said the victim was punched in front of his two children.

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The witness said the injured man was left "out cold with an uncontrollable bleed to the head".

He added: "To make matters worse, it took my mum [and] fiancé to see to the man’s bleed on his head.

"Two stewards watched on and failed to call for medical assistance. I had to run to get them myself.

"I hope the man is okay because as we left he was still bleeding from the head relentlessly and unconscious while his two sons watched on in tears and covered in blood begging for help."

The injured man is reported to be in his early 50s.

The witness added: "If any Saints fan out there knows this man could please let me know if he is well. My mum [and] fiancé are very shook and worried about his wellbeing."

Another social media user added: "We saw this, it was horrific!"

A police spokesperson said: "Officers arrested a 28-year-old man from Southampton on suspicion of grievous bodily harm with intent following the conclusion of last night's FA Cup game at St Mary's Stadium.

"This followed a report of an assault, in which a man in his 50s suffered a serious head injury.

"The arrested man remains in custody at this time."

The Daily Echo has requested a comment from Southampton FC and is awaiting a response.