Chelsea striker Diego Costa has been suspended from three domestic matches after a charge of violent conduct was upheld by the Football Association.Costa was involved in an incident with Arsenal’s Laurent Koscielny during Saturday’s 2-0 win over Arsenal in the English Premier league. The 26-year-old Spaniard put his hands in Koscielny’s face before clashing with Gabriel, who was sent off.Also read: Jose Mourinho helped me evolve as a player: Oscar “An FA charge against Diego Costa for violent conduct not seen by the match officials but caught on video has been found proven following an Independent Regulatory Commission hearing,” an FA statement said on Tuesday.”The Chelsea forward will, therefore, serve the standard penalty of a three-match suspension with immediate effect. The charge, which the player denied, was in relation to an incident involving Arsenal’s Laurent Koscielny in the 43rd minute of the game on Saturday.”Costa contested the charges. Chelsea said they were “disappointed” with the verdict.”We are extremely disappointed with the FA Regulatory Commission’s decision to suspend Diego Costa. We will await their written reasons before commenting further,” Chelsea said on Tuesday.