Aberdeen TV commentator Willie Garner believes the Dons were given a "different outcome" to Rangers on two identical incidents at Ibrox.
Saturday saw Jim Goodwin's side go down 1-0 to a later Kemar Roofe goal to make it no wins in 10 for the Dons across all competitions.
That run dates back to the Stephen Glass era but still leaves Aberdeen in 10th place in the Premiership with just eight wins all season.
But one of the club's TV staples believes the weekend game saw them punished unjustly while Rangers got away with one.
Co-commentating on Red TV, Garner said: "You could do that every time there's a free-kick happening: go and play the ball against someone and get him booked.
"Some referees don't punish it, some do."
Just seconds later Aberdeen were awarded a free-kick on the touchline and Ferguson looked to pass the ball across to Joe Lewis, only for Roofe to get in the way.
Garner insisted: "Ferguson's just been booked for doing the exact same thing.
"That's what Tavernier did with Ferguson and he (Ferguson) got booked for it and the exact same thing happens there and he doesn't get booked!"
The clip was posted by an Aberdeen fan, and Garner made clear: "My opinion has not changed. Identical incidents with different outcome."
He later agreed with another user who called it "bias".
