Maksim Chmerkovskiy has been a fan favorite on Dancing With The Stars for as long as anyone can remember. The older of the Chmerkovskiy brothers, Maks is often referred to as "the bad boy of ballroom."

Maks won season 18 of DWTS along with Olympic ice dancer Meryl Davis.

The professional dancer took some time off from the show here and there, but he's always been one of the main cast members. People have fallen in love with not only his dancing, but his personal life as well. Maks is married to fellow dancer Petra Murgatroyd, and the two welcomed a son, Shai, in January 2017.

This season, Maks is paired with TV host and former Miss America, Vanessa Lachey. It's just three weeks into the season, fans of the show may have noticed something wrong with this week's episode.

Maks was nowhere to be found this week, and the reason is pretty interesting.

Dancing With The Stars opened by dedicating the show to those affected by the Las Vegas shooting, and then co-host Erin Andrews made a big announcement to the audience.

"Maks is dealing with a personal issue so Alan is stepping in and dancing with Vanessa tonight," she said. Alan is a professional dancer who was eliminated the previous week.

However, sources told PEOPLE magazine that it's much more than a 'personal issue.'

"There's a big chemistry issue," the insider says. "They both have big personalities and that's not always the best recipe for a good partnership. They've been fighting a lot."

"I wouldn't be surprised if Maks doesn't return as her partner for the rest of the season," the insider continued.

This isn't the first time Maks has butted heads with his partners. In 2015, he revealed that his former partner, Olympian Hope Solo, is "just a sh***y person."

"That's literally the only person that I could dislike from my past, present or future," he said in an interview. People can be bad or good or whatever. You can have a s"”"“ life growing up. You can have a tough upbringing. You can have history. You can have whatever. But if you are just a bad person, you know what I mean? There's no excuse for that."

In Hope Solo's memoir, she claimed Maks was rough with her, even slapping her once during rehearsal. These claims were never corroborated.

But other former partners of Maks says he was great.

"I feel that I can really be myself with Maks," Meryl Davis said in 2014. "He pushes me to stand up for myself, whether it's in real life or on the dance floor. It's cool."

"The reason why Maks and I worked out so well was because I come from a world where all I worked with was men, and pretty much I'm like a guy in a lot of ways," current host and former contestant, Erin Andrews, said.

No confirmation has come from the show or Maks' reps on whether or not he will be leaving for the entire season, but we hope it's not true!