AN angle of the incident involving Andy Robertson and assistant referee Constantine Hatzidakis appears to show the linesman attempting to elbow the Liverpool man.
The Reds drew 2-2 with Premier League leaders Arsenal on Sunday afternoon in an action-packed clash at Anfield.
In a fiery encounter, perhaps the most astonishing moment came after the half-time whistle had blown.
Robertson was remonstrating with assistant referee Hatzdakis as the players and officials made their way off the pitch.
And a new angle circulating on social media seems to show the linesman aggressively moving his elbow towards the face of Robertson.
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A PGMOL statement confirmed the incident will be looked at.
It read: "PGMOL is aware of an incident involving assistant referee Constantine Hatzidakis and Liverpool defender Andrew Robertson at half-time during the Liverpool v Arsenal fixture at Anfield.
"We will review the matter in full once the game has concluded."
The officials were booed off by the crowd after exchanging stern words with Reds skipper Jordan Henderson, who protested his team-mate's case.
Sky Sports reporter Geoff Shreeves claimed that Robertson was furious as he entered the tunnel, accusing the official of "elbowing him in the throat".
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Gary Neville claimed that the incident was "not that bad".
But Neville's fellow ex-England international Chris Sutton called on Hatzidakis to be banned.
Appearing on BBC 5 Live, he said: "I really don't know what he was thinking. As far as I can see, he has to be banned.
"He will have to sit out a number of games. I can't remember another incident like this. Where is the precedent for these things?"
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The 2-2 draw leaves Arsenal six points clear of Manchester City at the top, although Pep Guardiola's side have a game in hand.
Arsenal will travel to City on April 26 for a huge title showdown at the Etihad.
