Speaking on It Takes Two, he explained that he was not angry with the former Emmerdale star and it was unfair to slam her when she had only been dancing for 10 weeks.
Host Zoe Ball reminded viewers at home of Shirley’s comment to Gemma: “You’ve got to get your devotion and motion to come out as emotion.”
She then revealed that they had made a mug for the soap actress with the criticism printed on it but Aljaž was far from impressed.
He hit back at the head judges’ remark, exclaiming: “It’s a lovely saying and it looks great on a cup but Gemma has been doing this for 10 weeks now.
“I knew from day one that it is going to be the hardest ballroom dance that we are going to tackle and with all the spins and all the turns, we had to fix the posture for her to be able to do it properly for her to have something to focus on in the room.
“And you know there might have been a moment in that dance that the face wasn’t fully engaged and portraying the story that there should have been. But, I think it was impressive for Gemma to get through a Viennese Waltz.”
Aljaž proceeded to hand the mug back to Zoe, adding: “There were so many steps and so many changes.
“So, I forgive my partner who has danced for 10 weeks that her face wasn’t engaged and so we’re going to put that mug here.”
It comes after Gemma broke down in tears on Saturday night as Shirley told her: “You messed up.”
Explaining her criticism, the head judge went on: “You had some fairly decent natural turns and you had some nice slows in there.
“Appreciate that with the music. But we had some mess up over here on the fleckerl!”
Strictly Come Dancing continues Saturday on BBC One at 6.45pm while It Takes Two airs weekdays on BBC Two at 6.30pm.