Nothing screams “college basketball rivalry” quite like the top player in the country’s mom cursing out a rival fan base.

During Duke’s victory over North Carolina, Cooper Flagg scored a slam dunk near the end of the game. Following the play, Kelly Flagg, Cooper’s mother, was caught on camera enthusiastically celebrating and possibly shouting an expletive towards any upset North Carolina fans nearby.

After the incident, Kelly took to Facebook and explained that her celebration was a mix of pride for her son and frustration towards the UNC fans for their behavior. She unapologetically expressed her sentiment towards the rival fans, showing support for Duke.

Flagg finished with 15 points, nine rebounds and six assists in the contest as the Blue Devils improved to 28-3 overall and 19-1 in ACC play.

The win helped catapult Duke into the No. 1 ranking on the latest AP poll.

“I do realize that it wasn’t my best look. However, if you actually know me and are a real friend of mine you weren’t shocked,” Flagg’s mom wrote.

She added some context behind what fueled her to become so feisty in the moment.

Kelly further described the unpleasant experience they faced from the UNC fans before, during, and after the game. She highlighted the harassment directed at her family and her son, as well as his teammates, painting a picture of a hostile environment created by some North Carolina supporters.

Rivalries are what make college sports so unique, and Flagg’s mother is just another example of how testy things can get — even for a mother of a family from Maine with no ties to Duke until this past year.

The 18-year-old Flagg currently projects as the consensus No. 1 pick in the 2025 NBA Draft and has the Blue Devils positioned for a deep NCAA Tournament run.