Hull substitute Boyd and England international Hart clashed foreheads with Hull substitute Boyd during an exchange in City's 2-0 win at the KC Stadium on Saturday.

The exchange took place when Boyd was denied a penalty after claiming to have been fouled by Hart.

Picture of the ensuing fracas appeared to show Boyd spitting at Hart.

Significantly, the alleged spitting was not seen by referee Lee Mason and an FA statement said: "Hull City's George Boyd has been charged by the FA following his side's game against Manchester City on 15 March 2014.

"The charge is in relation to an alleged breach of FA Rule E1 [a] in that in or around the 68th minute of the game Boyd spat at Manchester City's Joe Hart. The incident was not seen by the match officials."

Boyd has until 1800GMT Wednesday to respond to the charge.

Under a new pilot project in Premier League matches this season, if an incident has not been seen by the match officials, a three-man panel of former elite referees will be asked by the FA to review it and advise what, if any action, they believe the match referee should have taken had it been witnessed at the time.

For an FA charge to follow, all three panel members must agree it is a sending-off offence.

In this instance, the panel were of the unanimous decision that it was an act of misconduct.

Earlier, the FA said Hart would face no further disciplinary action as he had been booked by Mason and thus his case had been dealt with by the match officials.