Villa were already trailing to an early Anthony Gordon goal when Duran was involved in a coming together with Newcastle defender Fabian Schar.
As both players tumbled to the ground, they each seemed to make accidental contact with each other, but the incident concluded with Duran's studs going down Schar's back.
Referee Anthony Taylor controversially adjudged the action to be deliberate, despite the Colombia international being off-balance and limited as to where he could place his foot.
After the 3-0 defeat, Unai Emery stated that Villa will appeal the dismissal, one which brings with it a three-match suspension.
'It wasn't a rash decision'
The general consensus is that Duran was unfortunate to be sent off, yet Gallagher told Sky Sports News that he felt it was the correct decision.
Gallagher said: "I thought it was a red card. People say he's off balance because Schar's pulling him and that there's always going to be contact, but I thought he could avoid that. That's what Anthony Taylor has seen.
"What I like about it is that Taylor tracks it, sees what has happened, and takes his time. I don't have a problem with that as the ball is dead. He's probably got some input from the assistants and fourth official.
"He's taken his time, it's not rash. His right leg changes direction. That's what Anthony's seen. I can see that. The assistant said he'd seen it too.
"The decision was made in real time, nobody went to a monitor like a CSI breakdown. The process was about human beings making the right decision."
What games does Duran stand to miss?
As it stands, Duran is in a position where he will not be able to return to action until January 15.
Villa next face a Premier League double-header at home to Brighton & Hove Albion and Leicester City before playing West Ham United in the FA Cup third round on January 10.
The 21-year-old has recently enjoyed a run of starts for the West Midlands outfit and had scored in four successive games before the trip to St James' Park.
Written by
Darren Plant