Cape Town - Manchester United and Manchester City players and staff were involved in a violent post-match brawl in the Old Trafford tunnel leaving a member of Pep Guardiola's coaching staff with a bloodied face.

The Daily Mail reports that a mass brawl involving 20 players and staff took place after United manager Jose Mourinho approached the City dressing room and demanded players show respect and tone down their celebrations.

Mourinho who was leaving the United dressing room to conduct his post-match interviews approached the away dressing room and demanded the City players turn down their music.

United’s players felt that the away side had turned up their music to provocative levels and were going over-the-top in their celebrations.

Mourinho was confronted by City’s Brazilian goalkeeper Ederson leading to a shouting match between the two in Portuguese as they squared up to each other.

The incident quickly escalated after United’s players - who felt their opponents showed a 'lack of respect' - followed their manager to the City changing room where punches and bottles were thrown.

The United manager was hit in the head with a water bottle and doused with milk in the melee.

The Guardian revealed that Mikel Arteta, one of Pep Guardiola’s assistants was left with blood streaming down his face with Romelu Lukaku one of the players prominently involved.

Police officers and stewards had to separate the players and members of staff in the violent scenes and restore order according to witnesses.

Mourinho later made no mention of the incident to the cameras in his interviews with Arteta needing to receive medical attention.

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