Elland Road security were forced to remove an intruder who confronted Newcastle boss Eddie Howe during the clash with Leeds United.
BT Sport cameras captured the moment a member of the capacity crowd made their way up the touchline and into the technical area of the visiting boss. The flashpoint occurred in the closing stages of a thrilling 2-2 draw to start the Premier League weekend.
Newcastle were waiting to take a dangerous free-kick on the edge of the box after Junior Firpo was dismissed for a second yellow. Kieran Trippier stood over the free-kick, before the fervent crowd noticed the disturbance on the touchline.
Howe appeared to be shoved by the individual, before stewards escorted him off the pitch and down the tunnel at Elland Road.
It was a dramatic conclusion to a match filled with incident, which saw Leeds take the lead after just seven minutes. Sam Allardyce told his new charges that a win was imperative in their battle against the drop, and his message had an instant impact with Luke Ayling putting them in front.
The hosts were then given a golden chance to double their lead when Joelinton fouled Firpo in the area to concede a penalty. However, Patrick Bamford saw his poor spot kick saved by Nick Pope.
And Leeds were instantly made to rue that miss when Newcastle were awarded a penalty of their own less than two minutes later. Callum Wilson made such no mistake with his effort, stroking home his 16th league goal of the season.
That took the wind out of the sails of the home support and it went from bad to worse in the second half when Firpo inexplicably handled the ball in the box. Wilson was then coolness personified, slotting his penalty high into the roof of the net.
But with Leeds staring at a seriously damaging home defeat, Rasmus Kristensen fired them level when his shot was deflected off Kieran Trippier into the bottom corner of Pope's goal.
That wasn't the end of the drama though, with Firpo getting his marching orders in stoppage time, before the incident involving Howe and the supporter.
Speaking after the full-time whistle, Howe said: "I'm not sure if he pushed me. He confronted me, he said something I can't repeat and then he was led away. Moments like that do make you think. Safety is paramount and we need to be mindful."
The draw leaves Newcastle in third place, but just four points ahead of Liverpool in fifth having played the same amount of games. As for Leeds, they remain in the relegation zone, one point behind Everton in 17th, who have one game in hand.