Manchester United have been warned that they could be subject to a Football Association (FA) investigation, and possible points deduction, if they are found guilty of failing to control their players during the victory over Arsenal.

Tempers flared in the second half between the two clubs when on-field referee Andy Madley awarded a penalty to Arsenal for a foul on Kai Havertz by defender Harry Maguire. As the referee looked to clear the box for the spot kick to be taken, both sets of players were involved in a brawl on the pitch with Maguire and Gabriel Magalhaes looking incensed - following by some pushing and shoving.

Gabriel and Maguire were both booked in the incident, but it appeared that Manuel Ugarte used his head towards an opposition player in the aftermath but that was not spotted by the on-field officials. Speaking from his personal experience, former top-flight referee Keith Hackett told Football Insider that both clubs would be fortunate if they avoided an investigation and punishment moving forward,

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"The mass confrontation which may have also seen a player headbutting an opponent will be the subject of an investigation by the Football Association," he explained. "Years ago, I was in the middle of a mass confrontation involving what was a 21-man brawl.

"I decided not to red card anyone on the basis that I might have had more than a handful walking in the direction of the tunnel. So I submitted a detailed report to the Football Association, who investigated and both teams were deducted points.

"I have no doubt that both teams will be charged for failing to control their players. The question that we can ask - if VAR was in operation this would have been reviewed and the result may well have secured a different outcome."