"She's an amazing person," Chmerkovskiy, 33, told Us Weekly of the 21-year-old model. "We have an incredible time together, and, you know, I definitely didn’t see that coming and I think neither did she."
The former "Dancing With the Stars" contestant stressed that he was not expecting his relationship with Upton to take a romantic turn.
"We enjoy each other's company very much and like I said, she's a great girl that I never thought anything romantic like this could have happened," he explained.
Rumors that Chmerkovskiy was dating Upton began over the summer after the two were spotted having dinner at Scalinatella in New York. Last month, their relationship was confirmed after they were spotted holding hands in New York City's West Village on a Thursday afternoon.
2014: The Year in Music [PHOTOS]