Boxing painting is a kind of painting depicting a combat sport and martial art in which two people fight using their fists. Boxing is typically supervised by a referee engaged in during a series of one- to three-minute intervals called rounds and the boxers generally of similar weight. There are three ways to win if the opponent is knocked out and unable to get up before the referee counts to ten seconds (a Knockout, or KO) or if the opponent is deemed too injured to continue (a Technical Knockout, or TKO). If there is no stoppage of the fight before an agreed number of rounds, a winner is determined either by the referee's decision or by judges' scorecards. The two Ali versus Liston fights for boxing's world heavyweight championship were among the most anticipated, watched and controversial fights in the sport's history.Notable out-fighters include Muhammad Ali, Gene Tunney, Ezzard Charles, Willie Pep, Meldrick Taylor, Larry Holmes, Roy Jones Jr. ,Sugar Ray Leonard , Oscar de la Hoya, and Joe Calzaghe.