Manchester City striker Sergio Aguero was involved in an altercation with a supporter after Wigan's shock FA Cup fifth-round victory over his side.
City players were escorted off the field as Wigan fans ran onto the pitch at full-time to celebrate the 1-0 win.
Television footage appeared to show Aguero pushing a supporter away after being approached on the pitch.
Fans at the DW Stadium were seen ripping out advertising hoardings and throwing them towards police.
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Wigan chairman David Sharpe told BBC Radio 5 live: "It is not nice to see. Football is emotional, it is what it does to fans. But I don't like to see this at the end of the game.
"It is a massive result, but we have to stay classy in football. I don't like what I am seeing here."
Will Grigg's 79th-minute goal secured the win for League One Wigan over the Premier League leaders, who had Fabian Delph sent off for a tackle on Max Power in the first half.