Sergio Aguero has been banned for three games after the Football Association charged the player with violent conduct.
The striker was under investigation by the FA for elbowing Winston Reid during Sunday's Premier League clash between Manchester City and West Ham.
Although City protested, the FA panel found the player guilty of violent conduct.
The incident between the two players was initially missed by referee Andre Marriner and his officials during the match, prompting a subsequent review.
Aguero will now miss the Manchester derby on September 10, including City's following game against Bournemouth as well as their EFL Cup fixture against Swansea.
He will, however, still be able to feature in City's first Champions League fixture on Tuesday 13 September against Borussia Mönchengladbach.
A statement from the Football Association read: "Sergio Aguero will serve a three-match suspension with immediate effect after an FA charge of violent conduct against him was found proven.
"The Manchester City forward was involved in a 76th-minute incident with West Ham United's Winston Reid on Sunday [28 August 2016], which was not seen by the match officials but caught on video.
"The club denied the charge and submitted further that, if it was to be found proven, the standard punishment would be clearly excessive.
"On finding the charge proven at a hearing today (Friday 2 September 2016), an Independent Regulatory Commission went on to reject the club's further claim to decrease the three-match ban."
Aguero, who is not playing in Argentina's forthcoming World Cup qualifying double-header against Uruguay and Venezuela due to a calf injury, had made a superb start to the season, scoring six times in his first three appearances, including a hat-trick in a Champions League play-off win at Steaua Bucharest.
His form has helped Guardiola's side win their opening three games of the Premier League season, with United and Chelsea the only other teams with perfect records so far.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies