Videos on social media show a violent brawl erupt outside the Mudlark pub on Montague Close, London, just after 1pm on Saturday - ahead of Sunderland AFC and Millwall's EFL Championship fixture at The Den.
Large groups can be seen approaching the pub in the video, before surrounding the boozer.
The situation then escalated further and video footage showed fights break out involving multiple people, as reported by the Daily Star.
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Metropolitan Police said that one man was hospitalised as a result of the brawl, while another was arrested on 'suspicion of violent disorder' and remained in custody at a south London police station.
The match saw Sunderland earn a point and keep their play-off challenge on track.
Tony Mowbray's Black Cats earned a 1-1 draw at The Den, with sub Dennis Cirkin's header inside the final ten minutes cancelling out Jake Cooper's opener on the hour.
Read next:
- Premier League clubs tracking Sunderland goalkeeper Anthony Patterson
- Millwall boss Gary Rowett rages about two key decisions he felt cost victory against Sunderland
- Sunderland new boy Joe Gelhardt is relishing the challenge of filling Ross Stewart's shoes
- Sunderland boss Tony Mowbray on Dennis Cirkin's bravery and how it will cost him an FA Cup outing
- Sunderland's Dan Neil and Patrick Roberts stand out in draw at Millwall
