Former Premier League referee Dermot Gallagher has said he would be stunned if Constantine Hatzidakis lost composure in the alleged incident with Liverpool defender Andy Robertson.
At the end of the first-half in their top-flight crunch match, the Scotland captain was in discussion with the assistant referee on the near side. As the incident unravels, it appeared that the official raises his arm and catches the former Hull City full-back with his right elbow.
Sky Sports cameras caught the incident and as players walked off at half-time, Robertson as well as his teammates and Liverpool coach Vitor Matos were in heated discussions with Paul Tierney over what transpired. The 29-year-old was booked for his protests.
