Aston Villa captain Micah Richards has accepted an English Football Association charge of misconduct, an FA spokesman confirmed on Friday.
It followed an incident in the tunnel at the end of the Premier League defeat by Swansea City last Sunday.
Any sanction is unlikely to take effect before Monday’s match away to Tottenham Hotspur, the spokesman said.
The loss to Swansea was Villa’s sixth in succession and sent them to the bottom of the table. Manager Tim Sherwood was sacked the following day.
“I don’t want to envisage Villa in the Championship but it’s happened before,” caretaker manager Kevin MacDonald told a news conference on Friday.
“There’s no divine right to stay in the Premier League.
“Everyone has to push to get us out of this relegation battle. It starts now.”