Referee Darren Drysdale locked heads with Ipswich midfielder Alan Judge in an extraordinary exchange during their goalless League One draw with Northampton.
The official moved his head towards the Irishman in the final moments of the match and then briefly appeared to square up to the 32-year-old, before being ushered away by Northampton’s Lloyd Jones.
Judge, who had protested after being penalised for simulation, was then shown a yellow card, the fifth booking of the match.
In the third minute of stoppage time, Town’s Flynn Downes was sent off for violent conduct in an ugly end to the match.
Lowly Northampton defied the odds to secure a draw, but will be frustrated they only came away with one point instead of all three.
It lifted the Cobblers up two places, but they remain inside the relegation zone on goal difference. Ipswich, who finished with 10 men, moved up a place to 11th but are four points off the top six.
Ipswich keeper Tomas Holy had to gather a shot from Sam Hoskins and then hack clear after Troy Parrott’s loose pass was seized on by Mark Marshall.
Holy smothered Jack Sowerby’s effort and Luke Matheson blocked an effort by Hoskins while, with the half drawing to a close, Peter Kioso hit the post and Marshall pulled his shot wide.
James Norwood, who came on as a 71st-minute replacement for Ipswich, forced Northampton keeper Jonathan Mitchell into his first save of the game and to heap further misery on a woeful Ipswich, Downes was sent off in stoppage time.