"I never thought this would happen. I'm excited to be back," he says.
The fiery dancer, who often went toe-to-toe with the judges, insists there was never any bad blood between them.
"We had our run-ins but it's like [my brother] Val and me. We are the closest of people and obviously get into arguments," he says.
Chmerkovskiy, 33, says he was only passionate about protecting his teammate against the judges when he "felt that some things weren't very just." And now that he's joining Len Goodman, Carrie Ann Inaba and Bruno Tonioli on the panel, the pressure is on "to avoid being a hypocrite" after slamming their judging style.
"I have to be the person that I thought they should have been at the times I disagreed with their remarks," he says. "It will be interesting for me to see, 'Now you are in a position that you criticized before. Let's see you do better.'"
Chmerkovskiy, who appeared on 13 seasons of Dancing with the Stars, says viewers shouldn't be expecting him to take his hot-headed attitude to his judge's chair.
"I'm not going to be as critical because someone's kicks aren't as crisp as they should be because I know who I am looking at and I see what their potential is," he says. "I will do my best with constructive criticism and with giving positive reinforcement."
And while he acknowledges that fan favorite comedian Bill Engvall "isn't the best dancer this season" Chmerkovskiy says "there's something to be said about how much effort he puts into his performances."
Since leaving the show earlier this year, Chmerkosvkiy says "life is great." He’s been keeping busy with acting roles and spending time with his new girlfriend, model Kate Upton.
"She is extremely intelligent. We talk about everything including politics," he says. "She got everything pretty much herself and I respect that. I love how she can go from being girly to being a businesswoman in the snap of a finger."
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