Three-time Sprint Cup champion Tony Stewart confronted a heckler attending the Chili Bowl Nationals on Friday in Tulsa, Okla., and a video of their dispute quickly went viral.
Stewart, a two-time winner of the event who is not racing this weekend, went into the stands and put his hands on the fan's shoulders, which led the crowd to begin chanting "Tony."
The Lucas Oil Chili Bowl Nationals is a national event that attracts more than 300 racers of midget cars to the River Spirit Expo Center.
The confrontation happened in the general admission pit area grandstand on the backstretch.
Stewart and the heckler exchanged words and the fan appeared to push Stewart, who continued to yell at the fan for a few more seconds after another man moved the fan back into his seat.
Another angle of the encounter shows the fan telling Stewart, "I don't like you, and I never have."
The Tulsa County Sheriff's Office is investigating the conduct of the fan, identified in the video as off-duty sheriff's officer Kyle Hess.
Stewart is the 2002 and 2007 winner of the event and attended to help prepare the dirt surface. Stewart said earlier this week he might compete in the event again next year after he retires from Sprint Cup racing at the end of this season.
Stewart, who won NASCAR's Sprint Cup in 2002, 2005 and 2011, is known for his talent and his temper.
Stewart missed three races in 2014 after the sprint car he was driving hit and killed Kevin Ward Jr.
Ward was killed on Aug. 9, 2014 in an Empire Super Sprints race at Canandaigua (N.Y.) Motorsports Park when, after crashing, he approached the other cars on foot as they were riding around under caution. Stewart's car struck Ward, who was pronounced dead at a hospital 45 minutes later.
Ward's parents, Kevin and Pamela Ward, have filed a lawsuit against Stewart and seek unspecified damages for their son's pain and suffering as well as economic benefits and support he could have provided them.
Ward's family alleges that Stewart lost his temper to cause the tragedy and that, in the process of trying to intimidate their son, Stewart swerved toward him and ended up accidentally striking Ward.