Assistant referee elbow: Constantine Hatzidakis won't officiate until Andy Robertson investigation ends

Assistant referee Constantine Hatzidakis will not officiate until an investigation over an alleged elbow on Andy Robertson has been completed, the PGMOL has confirmed.

Hatzidakis was approached by Robertson as the half-time whistle blew during Liverpool's 2-2 draw with Arsenal on Sunday, with the defender insisting the assistant referee had struck him in the throat seconds later.

Robertson was given a yellow card by referee Paul Tierney for his role in the involvement, while Liverpool captain Jordan Henderson approached the officials to discuss the incident.

A statement from the PGMOL read: "PGMOL will not be appointing Constantine Hatzidakis to fixtures in any of the competition it serves whilst The FA investigates the incident involving the assistant referee and Liverpool defender Andrew Robertson at Anfield."

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Sky Sports' pitchside reporter Geoff Shreeves said: "Andy Robertson was absolutely apoplectic, stunned even.

"He said, 'The linesman has just elbowed me in the throat'. Jordan Henderson was well aware of it and led the remonstrations with referee Paul Tierney and after that they got taken away. Extraordinary scenes."

After the match, Liverpool manager Jurgen Klopp was unable to cast any light on the incident.

"I know it happened but I didn't watch it," Klopp said. "If it happened the pictures will speak for themselves."

The Professional Game Match Officials Limited (PGMOL) body, which governs referees in English football, has said it is investigating the incident, as is the Football Association.

A statement read: "PGMOL is aware of an incident involving assistant referee Constantine Hatzidakis and Liverpool defender Andrew Robertson at half-time during the Liverpool vs Arsenal fixture at Anfield. We will review the matter in full once the game has concluded."

Sky Sports pundit Gary Neville said if Hatzidakis is found guilty of striking the Liverpool defender, the official will end up in hot water.

"I've never seen an official raise an elbow to a player," he said while on co-commentary duty at Anfield. "I think he'll be in a lot of trouble after this game ends."

Ref Support UK believe Hatzidakis should be held to account but the rules need changing to stop players from crowding officials.

CEO Martin Cassidy said: "There are no clear boundaries, therefore, we believe there should be an exclusion zone of two metres around match officials to prevent aggressive contact. If this zone is breached the referee can issue an in-game sanction.

"That said, match officials are the Guardian of standards and must also be held accountable if found guilty of similar behaviour towards a player or any participant of the game.

"Any sanction issued to a match official must reflect the same sanctions issued to player and participant."

How the incident unfolded

Keane: Does Robertson pull assistant ref first?

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Watching the incident at half-time, Roy Keane questioned whether Robertson, whose side were trailing 2-1 to Arsenal at the time, actually grabbed the assistant referee first before the alleged elbow happened.

"I've not seen anything like it, really. But Robertson... does he grab the linesman first?" Keane said in the Sky Sports studio.

"I'm not sure. But Robertson's complaining. He should be more worried about his defending.

"I've watched Robertson a number of times and he is a big baby. Just get on with the game and concentrate on your defending. He does grab the linesman first."

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Meanwhile, Clinton Morrison added: "Robertson obviously grabs him, but he [the assistant referee] cannot react like that and throw an elbow.

"We won't hear the end of that. In all my years, I have never seen an assistant referee react like that.

"Players are quickly called out when they do stuff wrong, he has to apologise as that was out of order."

Ref Watch: Any different to Mitrovic? Warnock: It looks like assault

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Assistant ref drama Q&A

What happened, the next steps, what is Hatzidakis like, has this happened before, and could the ref have done anything differently?

Former Premier League referee Dermot Gallagher answered the key questions about the incident.

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