Swansea manager Garry Monk said "pretty much everyone" was involved in the tunnel brawl that broke out at the end of his side's 2-1 win at Aston Villa on Saturday.
Stewards went to the Villa Park tunnel to restore calm after bad feeling ignited by a first-half clash between Villa defender Micah Richards and Swansea counterpart Federico Fernandez reignited after the final whistle.
Both Villa and Swansea must wait to discover whether the Football Association will charge them over the postmatch disturbance, with officials waiting to see referee Neil Swarbrick's report on Monday before deciding whether to take action.
Swansea's win left Villa at the foot of the Premier League table and cost Villa manager Tim Sherwood his job.
And Monk told Wales online: "Obviously when you lose the game, emotions are running high. I think it was more to do with that rather than anything that happened individually.
"Whether it was Fede I don't know. I went into the changing room, and when I came out it was pretty much everyone [involved].
"I couldn't really see, so I don't know what was happening."