Constantine Hatzidakis: Assistant ref stood down after Andrew Robertson elbow incident

PGMOL said Hatzidakis would not take part in any fixtures while the English FA carries out its investigation into what happened during Liverpool's match against Arsenal at Anfield

Liverpool's Andy Robertson, left, remonstrates in front of assistant referee Constantine Hatzidakis during the 2-2 draw against Arsenal at Anfield. EPA

Assistant referee Constantine Hatzidakis has been stood down while the English Football Association investigates an alleged elbow on Liverpool defender Andrew Robertson.

The extraordinary incident occurred at half time during Liverpool's 2-2 draw against Premier League leaders Arsenal at Anfield on Sunday.

Robertson appeared to confront Hatzidakis on the pitch, reaching to grab the arm of the official, who reacted by jabbing his elbow towards the Liverpool left-back.

An irate Robertson gesticulated that he had been struck by Hatzidakis while he was led away by teammates, only to receive a yellow card by the match referee Paul Tierney in the aftermath of the bizarre incident.

Scotland captain Robertson had earlier been warned by Tierney for his attitude towards Hatzidakis.

A statement by the Premier League referees' body the PGMOL said Hatzidakis would not take part in any fixtures while the FA carries out its investigation.

"PGMOL will not be appointing Constantine Hatzidakis to fixtures in any of the competitions it serves whilst the FA investigates the incident involving the assistant referee and Liverpool defender Andrew Robertson at Anfield."

Keith Hackett, formerly head of the PGMOL, told BBC Radio Five Live: "Ultimately, if he is found guilty of this, his career is in jeopardy.

"I was trying to find an excuse as to why he did it and I came up with was he in fear? He shouldn't be, because he's in a protected environment with plenty of security.

"But he reacted in a way that he shouldn't have reacted at the end of the day and here we are talking about a match official and not a decision, but an action by a match official – and he's clearly lost his composure."

Sunday's ugly scenes follows recent incidents which have seen Fulham's Aleksandar Mitrovic handed an eight-game ban for his push on referee Chris Kavanagh, and Manchester United's Bruno Fernandes receive widespread criticism for nudging an assistant referee.

Liverpool boss Jurgen Klopp said he did not see what had happened, but Sky Sports pundits working on the game reacted with incredulity.

“I know it happened but I didn’t watch it,” Klopp said Sunday. “If it happened the pictures will speak for themselves.”

Gary Neville, the former Manchester and England defender, said: "I've never seen an official raise an elbow to a player. I think he'll be in a lot of trouble after this game ends."

Former Manchester United captain Roy Keane said of Robertson: "He should be more worried about his defending."

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