Gieschen said the free, paid against Russell for a marking infringement, was correct because the Blue had used his hands to push off Blair during the marking contest, rather than to hold his ground.
"[Russell] can stand his ground by using his forearm, his shoulder, his hip or his body," Gieschen told afl.com.au.
"But in actual fact he puts his arms out and he puts his two hands in [Blair's] chest, then he extends those arms and pushes off.
"So in that situation, rather than just holding his ground, he actually pushed in the marking contest, and as we know players cannot push, bump, block or hold in a marking contest.
"So the umpire paid a correct free kick for marking interference in that he pushed."
After receiving the free kick, Blair converted his set shot from 20 metres out to put the Magpies 24 points clear late in the second quarter.
From the same game, Gieschen admitted that the umpires missed an incorrect disposal by Carlton captain Chris Judd.
"I think the vision clearly shows that Chris Judd picks up the ball, he shapes to handball but, in actual fact, he just tosses the ball out," the umpires boss said.
Gieschen also addressed a holding the ball call against West Coast Eagle Shannon Hurn, a deliberate out of bounds by the Brisbane Lions' Daniel Merrett, and a 50-metre penalty against Gold Coast's Nathan Bock that put Bulldogs full forward Barry Hall on the goal line.
Watch the latest OPSM What's Your Decision? for Gieschen's verdict on each incident.
