Here is a video of the incident, courtesy of TMZ:
Horry was at the tournament watching his son. Witnesses told TMZ that Horry threw several punches at the man, who was supporting an opposing team, after being heckled and pushed by him.
The former Houston Rockets, Los Angeles Lakers and San Antonio Spurs star said: "The guy was trash-talking the whole game. He shoved me. Where I'm from, you protect yourself."
The 46-year-old added he opted to walk away as he was "the only one who was gonna lose in this situation" and said the man in question has been verbally abusive toward his son's team before.
A spokesperson for the basketball tournament had no comment on the fight or Horry's allegations.
Horry is a seven-time NBA champion and played in 244 career playoff games, an NBA record at the time before being surpassed by Tim Duncan and Derek Fisher.