Liverpool forward Ryan Babel is set to face disciplinary action by the Football Association (FA) after posting a mocked-up photo of referee Howard Webb in a Manchester United shirt.

The picture appeared on the Dutch forward's official page on social networking site Twitter just hours after United beat Liverpool 1-0 in the third round of the FA Cup, a match refereed by Webb, who was in charge of last year's World Cup final.

Webb angered Liverpool by awarding United a first-minute penalty from which Ryan Giggs scored the only goal of the game at Old Trafford before sending-off Steven Gerrard, the Merseysiders' captain.

An FA spokesman said: "We will definitely look into this matter."

As well as the photo, Babel wrote: "And they call him one of the best referees? That's a joke. SMH (shaking my head)." Babel, 24, subsequently apologised to Webb, saying of his Twitter 'followers': "My apology if they take my posted pic seriously. This is just an emotional reaction after losing."