The Hibees defender was given his marching orders by referee Nick Walsh in the 60th minute when he caught Borna Barisic with a wild, late challenge.
That sparked a strong reaction from the Rangers players – and a similar reaction from Steven Gerrard and his coaching staff.
Several members of the away dugout jumped from their seats to protest at fourth official Steven Maclean.
And they were met with a strong reaction from the Hibs dugout, with Jack Ross’ assistant manager John Potter at the front of those:
Both Potter and Rangers coach Tom Culshaw were sent off for their part in the scuffle.
Rangers had scored their third goal of the game just minutes before Porteous’ straight red card – with Jermain Defoe adding to goals from Ryan Kent and Joe Aribo in the first half.
If Rangers do grab all three points, it will take them back to two points off rivals Celtic at the top of the Scottish Premiership table.