The Football Association and the Professional Game Match Officials Limited, PGMOL, are looking into accusations that an assistant referee elbowed Andy Robertson during Liverpool’s 2-2 draw with Arsenal on Sunday.
Roberton approached Constantine Hatzidakis as the half-time whistle blew and the Liverpool defender insisted the official had struck him in the throat seconds later.
Referee Paul Tierney showed Robertson a yellow for his protests, as the two teams disappeared down the tunnel.
PGMOL, which oversees referees in English football, has said it is investigating the incident, as is the FA.
“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,” a statement read.