During Monday night's game between the Oklahoma City Thunder and Utah Jazz at Vivint Smart Home Arena in Salt Lake City, Russell Westbrook was involved in a verbal altercation with a heckler.

In footage posted on social media, Westbrook can be seen responding, "I'll fuck you up. You and your wife. I'll fuck you up." After the game, Westbrook explained to reporters that the fan had told him "to get down on my knees like you used to."

The heckler, later identified as 45-year-old Shane Keisel, maintains that he did nothing wrong. Of course.

Following Utah's 98-89 loss, Keisel told ESPN the exchange "started off as fun" with him yelling at Westbrook to "ice those knees up!"

According to Keisel, after Westbrook replied that it was "heat on his knees," Keisel responded, "You're going to need it." He also claims his wife, Jennifer Huff, didn't participate in the exchange.

"He just went nuts," Keisel told ESPN. "She never got up. She never stood up. She never said a word to him. I mean, it's all fine, we're having fun and games with the guy and we're talking, but at the end of the day, no man should threaten a woman, period.

"I'm not afraid of the guy. Come on up. But when you threaten a woman that's 5 feet tall and 110 pounds, you're a big man. So this guy needs to be exposed."

According to ESPN, Keisel and other Jazz fans were issued warning cards for "excessive verbal abuse" that was in violation of the NBA fan code of conduct. Check out the "warning card," as well as some of Keisel's old tweets, below.