LONDON (AFP) - Chelsea's Marcos Alonso has been charged with violent conduct by the Football Association (FA) after an incident during the English Premier League football match against relegation-threatened Southampton.

The left wing-back appeared to stand on the back of Southampton striker Shane Long's leg during Saturday's game but the incident went unpunished by referee Mike Dean.

However, the FA has since reviewed footage and sanctioned the Spaniard, who has until 1700 GMT on Wednesday (1am on Thursday April 19, Singapore time) to respond.

Alonso is facing a three-match ban if he accepts the charge, which would rule him out of Sunday's FA Cup semi-final, also against Southampton, and Premier League games against Burnley, on Thursday, and Swansea.

"Chelsea's Marcos Alonso has been charged with violent conduct following an incident with Southampton's Shane Long," an FA statement said.

"It happened in the 43rd minute of Saturday's game... and was not seen by the match officials but caught on video."

Off-the-ball incidents not seen at the time are referred by the FA to a panel of three former elite match officials. For retrospective action to be taken, and an FA charge to follow, the decision of the panel must be unanimous.

Southampton boss Mark Hughes condemned the tackle at the time, saying it should have resulted in a red card.