After the goalless draw at Old Trafford in the 31st round of the Premier League on Sunday, Grealish was approached by a Man Utd supporter near the tunnel. The fan, after waving the Man City player over, suddenly slapped him.
Police immediately arrested the fan, identified as 20-year-old Alfie Holt. He has been charged with assault and is scheduled to appear in court in Manchester this July. Fortunately, Grealish was not injured in the incident, Daily Mail reported.
Tensions were high throughout the match, with Man Utd fans also directing insults at the mother of Man City star Phil Foden.
City manager Pep Guardiola expressed his frustration after the game: "It's a lack of class. But the issue isn't with Manchester United as a club, it's with the fans. Honestly, I don't understand what was going through their minds. They should be ashamed of their behavior and lack of respect."
The draw was a disappointing result for Man City, who struggled against a United side deep in crisis. Guardiola's team are currently sixth in the Premier League with 52 points from 31 games, just one point behind fourth-placed Chelsea and fifth-placed Newcastle, who still have a game in hand. Failure to break into the top five could see City miss out on next season's Champions League.
Meanwhile, Man Utd are in 13th place with 38 points, trailing the European tournament spots by 14 points. The Red Devils are enduring their worst season after Sir Alex Ferguson.