As a couple that seemed in it for the long run, it comes as quite a shock that Karina Smirnoff and Maksim Chmerkovskiy have called it quits.

People magazine is reporting that the “Dancing With The Stars” professionals have broken up after dating for a year.

“I can confirm that this is true,” the rep tells the magazine. No reason was given and the rep says no further statement would be issued. Chmerkovskiy’s rep didn’t immediately comment.

Smirnoff, 31, and Chmerkovskiy, 28, who became engaged in December, had planned on getting married in June 2010, but prolonged their engagement in July because of their busy Broadway schedules.