Burnley said on Sunday that defender Erik Pieters was subjected to online abuse after Saturday's 1-1 Premier League home draw with Arsenal in which the Dutchman was sent off before getting a reprieve from the Video Assistant Referee (VAR).
Arsenal felt they should have had a penalty when the ball hit second-half substitute Pieters' arm in the box and shortly afterwards he went close to putting his side ahead with a volley that was tipped over the bar by Bernd Leno.
Pieters was then sent off for handball when he cleared a goalbound Nicolas Pepe shot in the penalty area but VAR overturned referee Andre Marriner's decision to show him a red card and award Arsenal a spot kick.