A sucker punch (American English), also known as a coward punch, or cold-cock (American English), is a punch made from behind without warning, allowing no time for preparation or defense on the part of the recipient. The term is generally used in situations where the way in which the punch has been delivered is considered unfair or unethical. In practice, this often includes punches delivered from behind. While the one hit punch or king hit (Australian English) is a different style of one-on-one fighting where the recipient is knocked out in one punch - that is, pitting one individual against another. It can be considered as a sucker punch when the recipient is not expecting it, or if they are unevenly matched by weight, which some people use to help strengthen the amount of force used.
In boxing, a sucker punch thrown outside of the rules is illegal. For example, when James Butler knocked Richard Grant unconscious after losing a fight to him on points, his license was suspended. Because sucker punches come unexpectedly, people at risk of such blows must be alert to the proximity of potential opponents.
During 2013 and 2014, significant media attention was paid to two violent killings involving one-hit punches in Australia. Noting that 91 people had died in Australia in the previous four years from brain trauma as a result of being king hit, a media campaign was launched to refer to them as coward punches. This campaign was supported by the New South Wales Government.
The sucker punch has been adapted into many films, video games and other forms of media. It can be used to show the antagonist's vileness, the low morals of an anti-hero, betrayal of someone close to the protagonist, etc. However, it also can be used as a weapon of the protagonist to deal with an unfair situation. A sucker punch is a major dramatic element in the 2004 film Million Dollar Baby.
Australian soap operas Neighbours and Home and Away have covered the topic in storylines broadcast in September 2014 and October 2015 respectively.