Manchester City striker Sergio Aguero was spat and sworn at by a Wigan Athletic fan during the pitch invasion that followed their FA Cup tie, sources close to the player have told ESPN FC.
Television footage showed Aguero raising his arm to push away a supporter as hundreds of fans ran onto the pitch after League One side Wigan's 1-0 win at the DW Stadium.
Aguero will not face an investigation from the Football Association over his involvement in the incident, other sources told ESPN FC.
But the striker told club officials that the supporter shouted abuse at him before spitting, prompting his angry reaction. Aguero was restrained by Wigan defender Chey Dunkley, to whom he had been talking after the full-time whistle.
The striker and City could potentially make a complaint to police over the matter, although sources said no decision on this has been made.
Aguero's son, Benjamin, had been in the away end celebrating his ninth birthday.
Referee Anthony Taylor's report will be studied, with police also potentially involved if a complaint is made by either party.
City defender John Stones told reporters: "It is never nice to see that happen if the opposition team were on the end of it, but we were on the end of it. Obviously the home fans were coming on the pitch. It is never nice to see."
The Football Association is investigating four separate incidents from Monday's cup tie, sources have told ESPN FC.
A fifth incident -- the first-half red card issued to City midfielder Fabian Delph for a late challenge on Wigan's Max Power -- will not be reviewed, with Taylor's decision leading to an automatic three-match suspension for violent conduct.
However, the FA will take no action against any players or coaching staff from either team after an argument in the tunnel at half-time, with City coach Pep Guardiola and Wigan boss Paul Cook appearing to jostle each other.
The postmatch scenes that saw hundreds of supporters run onto the playing surface could lead to Wigan being punished by the FA, and the League One club will be asked to provide observations and explain their security procedures.
Sources said City will seek an explanation from Wigan about how the pitch invasion was allowed to happen, with players' safety put in danger.
Wigan expressed their displeasure at supporters invading the pitch in a statement, and chief executive Jonathan Jackson said that the club would investigate.
"Whilst we appreciate that the vast majority of supporters who ran on to the pitch did so spontaneously to celebrate a famous victory, we were disappointed with the action of a minority of supporters who acted in an inappropriate manner," Jackson said.
"Player and staff safety is of paramount importance, and we will conduct a full investigation."
An advertising hoarding thrown from the City section, which appeared to hit a police officer, will also be studied.
Police have confirmed that two arrests were made, on suspicion of affray, following an incident outside the stadium.