Karina Smirnoff and Maksim Chmerkovskiy
REX USA; Globe
04/16/2013 at 03:15 PM EDT
It appears Karina Smirnoff and Maksim Chmerkovskiy have buried the hatchet.
The formerly engaged pair
, who didn't have much interaction after calling it quits
in September 2009, shocked viewers on Monday night's Dancing with the Stars
when they not only shared a routine together
but looked happy about it.
"It was so fun," Smirnoff, 35, told PEOPLE backstage after the show. "It was drama-less and so refreshing. I enjoyed it. I really did."
Smirnoff – who says she was shocked when she opened an envelope and found out that Chmerkovskiy, 33, would be joining her and partner Jacoby Jones – admitted, "It was a little awkward in the beginning, but once we started, it was great."
Moving forward, the exes are in a friendly place.
"It's back to where it should be – professional and fun," Smirnoff says. "We're wearing heels, rhinestones and spandex. Let's put everything into perspective."
Chmerkovskiy, who left ABC's hit show as a regular this year to pursue other opportunities
, also dated
pro, Peta Murgatroyd.