"Poor sportsmanship" refers to the behavior of a person who does not act fairly, respect others, or show good attitude during a sports competition or game. Full definition
The objectionable behavior may be a demonstration of poor sportsmanship toward the other team or verbal abuse of a player who makes a mistake. (thespruce.com)
According to a survey by the National Association of Sports Officials (NASO), 76 % of the survey respondents report poor sportsmanship by parents as the single biggest reason officials quit. (nays.org)
Well, it goes back to the same question: Since both sides and their fans all generally pray to the same God for victory, is making an obvious point of thanking God for favoring your team because of your better performance just rubbing it in, thus const.ituting poor sportsmanship? (religion.blogs.cnn.com)