It’s a surprising admission from someone whose new film, “I, Tonya,” opening later this month, is all about the world of ice skating — in particular, the 1994 Winter Olympics, the toxic rivalry between Nancy Kerrigan and Tonya Harding, and the famous kneecapping incident that sent Ms. Kerrigan to the floor, screaming, “Why, why, why?”

Mr. Stan, perhaps best known to film audiences as Bucky Barnes (a.k.a. the Winter Soldier) in Marvel’s “Captain America” films and the coming “Avengers: Infinity War,” plays Jeff Gillooly, Ms. Harding’s husband at the time and one of the bumbling accomplices in the tabloid-ready crime. (In 1994, Mr. Gillooly was sentenced to two years in jail and fined $100,000 for his role in that incident; he was released in 1995. Ms. Harding was put on probation for three years and banned for life by the United States Skating Association.)

It is not a particularly sympathetic role. In fact, Mr. Stan, in character as Mr. Gillooly, is introduced to the film’s viewers in an early scene in which he looks directly into the camera and says: “At 27 I was the most hated man in America. Maybe the world — with a mustache I still can’t apologize enough for. My name was a verb. Like, if you bash someone in the kneecap, you ‘Gillooly’ them.” (Margot Robbie plays Tonya in the Oscar-buzzy movie, which was directed by Craig Gillespie.)

Was there any trepidation about taking on the role of this somewhat unsavory character, one who is not only a comically inept criminal but is also part of a mutually abusive relationship that the film portrays unflinchingly?