Chelsea have pronounced themselves "extremely disappointed" after striker Diego Costa was handed a three-match ban for violent conduct during Saturday's 2-0 win over Arsenal.
An FA Regulatory Commission made the ruling on Tuesday just hours after Gunners defender Gabriel won his appeal against a red card for confronting Costa after the incident in question.
Costa had denied a Football Association charge over the incident, not seen by referee Mike Dean, in which he appeared to raise his hands to Gunners defender Laurent Koscielny.
Costa's antics were widely criticised within the game but Jose Mourinho was eager to stress his player's innocence and will no doubt have more thoughts to add to the terse statement issued by the club on Tuesday night.
It read: 'We are extremely disappointed with the FA Regulatory Commission's decision to suspend Diego Costa. We will await their written reasons before commenting further."
Both clubs still face an outstanding charge of failing to control their players, while Gabriel faces an additional charge of improper conduct for his reaction after being shown the red card by referee Mike Dean.
An FA statement read: "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.
"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 [19 September 2015]."
However, the FA announced in a separate statement that it had accepted Arsenal's challenge to the red card issued to Gabriel and withdrawn his three-match ban with immediate effect.
Costa's antics on Saturday had provoked a furious response, initially from Wenger, who had indicated he had little faith in the appeals process.
Wenger said: "That (retrospective action) is the least they could do, but he (Costa) will do the same again next week and the week after and he always gets away with it."
Meanwhile, Chelsea team-mate Kurt Zouma unwittingly found himself at the centre of a storm after saying in a television interview that Costa "likes to cheat a lot".
Zouma later said on Twitter that he had not meant to accuse Costa of cheating and the club issued a robust statement insisting Zouma's use of his second language had been misinterpreted.
Diego Costa is facing a three-game retrospective ban after being charged with violent conduct by the English FA for putting his hands in the face of Laurent Koscielny during Chelsea's 2-0 victory against Arsenal last Saturday.