OXFORD UNITED manager Karl Robinson has accused a member of Sunderland’s coaching staff of head-butting his goalkeeper, Jack Stevens, during the half-time interval of today's fractious encounter at the Stadium of Light.

On a dramatic afternoon that saw Oxford finish with ten man after Mark Sykes was dismissed for two yellow cards, goals from Lynden Gooch, Aiden McGeady and Max Power enabled Sunderland to come from behind to claim a crucial victory.

However, events on the field were overshadowed by an unsavoury incident in the tunnel at half-time that was repeated at the final whistle.

While the exact nature of what went on remains unclear, it is clear that members of both teams’ playing and coaching staff clashed in the tunnel area, with Robinson alleging that Stevens was head-butted during the half-time fracas.

The Oxford manager has suggested that the police could get involved in looking into the incident, which could have serious footballing repercussions if the FA also decide to launch an investigation.

“My goalkeeper, he was head-butted at half-time,” said Robinson. “There was a massive brawl in there. It’s not just allegations, we have asked the police to come.

“Their players have seen it, our players have seen it. My player certainly felt it. But for some unknown reason there is no footage. Ironic here, isn't it? This club has had cameras for the last two years than any other club in football, yet there’s no cameras down in the tunnel at half-time.”

Sunderland manager Lee Johnson was made aware of Robinson’s accusations, but warned the Oxford manager to be careful as he felt some of the visitors’ coaching staff overstepped the mark themselves as tempers flared again after the final whistle.

“He’s (Robinson) got to be careful, I’ll tell you that,” said Johnson. “When it comes to the narrative of any argument, there are always two sides to any story. Let me tell you, there was a lot of Oxford staff that didn’t come out of it smelling of roses, let’s just say that.

“I didn’t see the first incident (at half-time), but I saw the second one and, for me, it was really stepping over the mark. So, I think there’s a bit of deflection in there from a few people.”

Referee Trevor Kettle sent Robinson to the stands after the Oxford manager complained about the quick free-kick that led to Sunderland’s second goal, but did not take any action over the half-time brawl.

It remains to be seen whether he mentions events in the tunnel in his post-match report, but while Johnson admits he was not impressed with some of the unsavoury scenes, he nevertheless felt it was important his players and staff stood up for each other.

“Genuinely, I didn’t see what happened at half-time,” he added. “I was in the toilet, waiting for the boys in the dressing room wondering where everybody was. It was probably a good thing because I would have been like Scrappy Doo in there.

“Look, it happens all the time, especially in a condensed area. It was handbags a lot of it. It happened at the end as well, which is not ideal, and I think that one was provoked, to be honest with you.

“As a football club, I want us to act with class, but I also want us to look after each other when there’s moments. Today, we had to look after each other in that tunnel because it was an incident that wasn’t great to see, but at the same time, probably not worth being blown out of proportion because not a lot happened.”