The Football Association have launched an inquiry after a referee locked heads with Ipswich midfielder Alan Judge last night.

Darren Drysdale moved his head towards Judge in a heated exchange in the final moments of the Tractor Boys' 0-0 draw with Northampton in League One.

Judge was protesting after being penalised for simulation in the box and was shown a yellow card after the pair were separated by players from both sides.

It was the fifth booking of the match and Ipswich's Flynn Downes was sent off for violent conduct in the third-minute of stoppage-time in an ugly end to the contest.

"It should have been a penalty on Judgey at the end but it is a results business," said Ipswich boss Paul Lambert. "The aftermath of that incident needs to be looked at."

Speaking the morning after the game on TalkSport, Lambert added: "I've text 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."