Joe Hart can count himself lucky to have stayed on the pitch during Manchester City's 1-0 win over Manchester United on Sunday, after appearing to square up to referee Michael Oliver.
Hart was livid after Chris Smalling attempted to block his goal-kick, for which the defender received the first of his two yellow cards.
Images show Hart making contact with Oliver's forehead with his own, but the whistle blower didn't flinch and appeared to brush off the incident.
It is possible Hart could face FA punishment.
City won the match thanks to Sergio Aguero's 63rd-minute strike.
It's not the first time that the fiery Hart has kicked off during a match, see the video below of the goalkeeper boot an advertising board in frustration when playing for England during the World Cup.
*WARNING: Video contains offensive language*
United manager Louis van Gaal said after the match that Smalling's sending off was stupid.
"In a derby you have to be careful - the second yellow card is a stupid yellow card," Van Gaal told the BBC."
"The sending-off is not one of those things. As a player you have to control your aggression.
"I didn't see the first yellow but with the second, you know you already have a yellow, so have to handle it differently. I said that to the players."
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