No contest (abbreviated "NC"), or no decision ("ND"), is a technical term used in some combat sports to describe a fight that ends for reasons outside the fighters' hands, without a winner or loser. The concept carried over to professional wrestling, where it is far more common, usually scripted to further a feud, generate heat and/or protect a push.
In the 1800s and early parts of the 1900s, many countries (and some parts of the United States) officially banned boxing, and occasionally the police would step in to stop the unlawful bouts (which, although unlawful, were still sanctioned by regional boxing commissions). Since boxing is now lawful almost everywhere in the world, the number of fights called no contest has decreased dramatically since the beginnings of the 20th century. Referees were also known to stop bouts during this period, when they felt bouts were too slow due to lack of aggression from one or both boxers.
In the modern game, the various rules that dictate whether a fight should be called a no contest, a disqualification, or a knockout differ between countries and boxing organizations. Rules in the United States now dictate that any bout which ends prior to the completion of the 4th round, due to an accidental headbutt, is to be declared a no contest. Prior to this, accidental headbutt stoppages had been ruled a technical draw. Most other no contests in boxing occur when unusual circumstances, which would include instances such as a bout being rained out, ring falling apart, or an unexpected injury caused by something outside of the boxer's control. One good example of an unusual circumstance occurred in 1983, on the undercard of the fight where Roberto Durán beat Davey Moore for the World Jr. Middleweight title at the Madison Square Garden, when Luis Resto and Billy Collins Jr boxed ten rounds. Resto appeared to win the fight cleanly, and the scorers gave the match to Resto. But, it was later discovered that he had cheated by tampering with his gloves before the fight. The injuries Collins received affected his sight, and, upon finding out what Resto and his corner had done, the New York State Athletic Commission decided to change the result of the fight to a no contest.