Tuesday 19 March 2019 18:10, UK
The FA are investigating allegations a coin was thrown at Chelsea's Ross Barkley during Sunday's game with former club Everton.
Sky Sports News understands the FA were made aware of the incident and have written to both clubs for their observations.
An Everton statement read: "We are investigating the alleged incident and reviewing footage.
"If anyone is found responsible for this or other such incidents, the club will take robust action."
Barkley was making his first appearance at Goodison Park since he left to join Chelsea for £15m in January 2018.
Everton won the game 2-0, following second-half goals from Richarlison and Gylfi Sigurdsson.
The alleged incident came two days after the FA, Premier League and EFL issued a joint statement, urging "all supporters to carefully consider their behaviour" at the weekend's games and "all games in the future".
That statement followed high-profile incidences of crowd trouble the previous weekend, including Aston Villa captain Jack Grealish being punched by a spectator who ran on to the pitch during their derby game at Birmingham on March 10.
Manchester United defender Chris Smalling was then shoved by a pitch invader during his side's match with Arsenal later that day.
