• Both clubs have until 6pm on Wednesday to provide an account of the fracas • Clubs dispute roles played by Romelu Lukaku and Vincent Kompany

Manchester United and Manchester City are at loggerheads regarding the scuffle in the Old Trafford tunnel on Sunday night, with the Football Association expected to receive contrasting accounts of the incident from the clubs.

United and City have until 6pm on Wednesday to provide the FA with their versions of a fracas that involved up to 20 players and staff from the clubs in the aftermath of the 2-1 win Pep Guardiola’s side achieved against José Mourinho’s team. Each club believe the other to be culpable for the incident. The FA can request CCTV footage from United should this exist and the governing body believes this will help clarify what happened. While the City coach Mikel Arteta was left with blood on his face, the cause of the injury remains unknown.

José Mourinho in post-match fracas over Manchester City’s ‘noisy’ celebrations Read more

City’s stance on the outbreak of the incident, it is understood, is that Mourinho behaved provocatively by approaching and then entering their dressing room, which was situated in a narrow corridor along from United’s. The Portuguese is viewed as having reacted adversely to his team’s defeat, with one onlooker informing the Guardian that the manager became angry with the City goalkeeper Ederson, saying: “You fucking show respect. Who are you?”

City believe this led to the bust-up and that Romelu Lukaku was prominently involved, too.

However, privately United are insistent the Belgium striker was not a prime mover in the brawl and that City’s behaviour was disrespectful, even earlier on, with claims “the walls were shaking” from the music being played in their dressing room before kick-off. This sense was subsequently compounded by Mourinho being adamant that City players celebrated the win too noisily.

Quick guide Tunnels of grudge Show Hide Battle of the buffet Manchester Utd v Arsenal (24 Oct 2004): United ended Arsenal’s 49-match unbeaten run with a 2-0 victory, but controversy surrounded a penalty and tempers flared after. Among the pushing and shoving, Sir Alex Ferguson was hit by a slice of pizza which Cesc Fàbregas finally admitted this year to throwing. Clash of the captains Arsenal v Manchester Utd (1 Feb 2005): Television cameras captured the pre‑match showdown between Roy Keane and Patrick Vieira, with the United captain pulled away from his Arsenal counterpart by referee Graham Poll, which set up an exhilarating game won 4-2 by the visitors. Pundit piles in Manchester Utd v Reading (12 Aug 2007): Dave Kitson had been on the pitch for 37 seconds when he was sent off for a late tackle on Patrice Evra. Waiting for him in the tunnel was Sky's Ruud Gullit, who felt the challenge deserved a 'double red card' – an opinion that did not go down well. Villains at Villa Aston Villa v Swansea City (24 Oct 2015): Micah Richards and Federico Fernández clashed during Swansea’s 2-1 win, a result which cost Tim Sherwood his job, before members of both teams clashed in the tunnel as stewards rushed in to calm the situation. Photograph: Sky Sports/PA/PA

While United allege that Vincent Kompany had to be “restrained” as tempers boiled over, with there being some disquiet at United that the visiting team captain should behave in this manner.

However, City are in no doubt that Kompany did not have to be held back. They believe, too, that they were fully within their rights to celebrate as they did, especially as the victory stretched the leaders’ advantage over second-placed United to 11 points with 16 matches played. There is also a view that Mourinho reacted adversely purely because of the loss.

In the buildup to the fixture the Portuguese accused City’s players of going down too easily and of committing tactical fouls. “If you ask me one thing that I don’t like a lot, it’s that they lose balance very easily. A little bit of wind and they fall,” he said.

Mourinho and Guardiola have previously endured difficult relations when in charge of Real Madrid and Barcelona, respectively. Sunday’s disagreement is the first sign of further strained relations since they took charge of United and City in summer 2016, each having been at pains to portray their relationship as cordial until now.