The Knicks–Nuggets brawl was an on-court altercation at a National Basketball Association (NBA) game between the New York Knicks and Denver Nuggets at Madison Square Garden in New York City on Saturday, December 16, 2006. This altercation became the most penalized on-court fight in the NBA since the Malice at the Palace, which occurred on November 19, 2004.

The fight began with a flagrant foul by Knicks guard Mardy Collins on Nuggets guard J. R. Smith in the closing seconds of the game. Several players joined in the confrontation and began to make physical contact. The fight briefly spilled into the stands, and also stretched to the other end of the court. All ten players on the floor at the time were ejected after the altercation was finished. When suspensions were announced, seven players were suspended without pay for a combined total of 47 games.

Although they were not penalized, Nuggets coach George Karl and Knicks coach Isiah Thomas were both scrutinized for their part in the brawl, while Nuggets forward Carmelo Anthony was criticized for harming his image as a star. Several writers said the NBA had penalized the players excessively because it wanted to keep its image free from violence.