Conor McGregor was scheduled to appear on an episode of the History Channel's "Vikings," but apparently had a change of heart.

Katheryn Winnick, who plays Lagertha on the show, told TMZ Sports that McGregor canceled his appearance just hours before he was supposed to shoot his scene. Winnick directed the episode and had written a role specifically for the UFC star.

"I wrote him a role with the writers, we came up with a role, and it just didn't work out," Winnick said. "Any change as a director, I have to change the entire scene ... and I had less than a few hours to change a whole scene."

Winnick appeared in good spirits about the situation, though she's still waiting on an apology from McGregor.