Ipswich manager Paul Lambert has urged the EFL to investigate referee Darren Drysdale's confrontation with his player Alan Judge during Tuesday's League One match against Northampton.
The 49-year-old Lincolnshire official appeared to square up to Judge and lean his head into the Republic of Ireland international after the midfielder's appeal for a penalty had been turned down.
Former Celtic star Lambert told talkSPORT on Wednesday: "I've texted Mike Jones (EFL head of referees) this morning to say, 'Have a look at the footage of the head thing'.
"To me, in my opinion, it looks as if the referee went in there and I said to him after the game, 'Did you put your head in my player?'
"He couldn't answer it and that's the reason I spoke to Mike. I haven't seen that in a long, long while."
The incident happened in the closing stages of the goalless draw at Portman Road.
Ipswich pair Flynn Downes and Jack Lankester and Northampton defender Lloyd Jones stepped in and calmed the situation before Drysdale booked Judge.
The FA confirmed on Wednesday morning it is aware of the incident.
Drysdale, who was appointed to the National List of referees covering EFL games in 2004, has also been a FIFA and UEFA assistant referee and was an assistant referee at the 2000 FA Cup final.
