Midfielder Ross Barkley, a Toffees academy graduate, was making his first appearance at Goodison Park since his acrimonious departure in January 2018 and the incident reportedly occurred at a Chelsea corner in front of the Gwladys Street End early in the first half.

No-one was hit by the object and Everton are looking into the matter.

“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,” said a statement from the club.

The Football Association is also investigating, Press Association Sport understands.

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 when Aston Villa captain Jack Grealish was punched by a spectator who ran on to the pitch during their match at Birmingham and Manchester United defender Chris Smalling was shoved by a pitch invader during his side’s match with Arsenal.

Aston Villa captain Jack Grealish (right) was punched by a spectator at Birmingham (Sky Sports/PA)

Meanwhile, Everton manager Marco Silva has been fined £12,000 after accepting an improper conduct charge for his behaviour after the defeat to Newcastle earlier this month.

The Portuguese was furious the hosts’ winning goal in their 3-2 victory at St James’ Park was allowed to stand as Salomon Rondon, who touched the ball on to goalscorer Ayoze Perez, was among a number of players offside in the build-up.

Silva confronted referee Lee Mason on the pitch and then turned his anger towards the assistant who had not raised his flag.

Marco Silva was fined £12,000 after accepting an improper conduct charge for his behaviour at Newcastle (Peter Byrne/PA)

“When they scored the third goal it was a big mistake by the assistant – it was a clear offside…it’s not just one or two players in offside positions, there were five Newcastle players in the same line in offside positions,” Silva said afterwards.

His venture on to the pitch resulted in a FA charge and led to the fine by an independent regulatory commission.

“The Everton manager accepted an improper conduct charge from The FA, which resulted from his behaviour on the field of play at the end of the Premier League fixture against Newcastle United on March 9,” a statement from the FA read.

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