Soccer (known as football throughout most of the world) is a team sport played between two teams of eleven players, and is the most popular sport in the world.
The game is played on a rectangular grass or artificial turf field, with a goal in the centre of each of the short ends. The object of the game is to score by driving the ball into the opposing goal. In general play, the goalkeepers are the only players allowed to use their hands or arms to propel the ball; the rest of the team usually use their feet to kick the ball into position, occasionally using their torso or head to intercept a ball in midair. The team that scores the most goals by the end of the match wins. If the score is tied at the end of the game, either a draw is declared or the game goes into extra time and/or a penalty shootout, depending on the format of the competition.
Tom Stone's sons were avid soccer players. During the Stones' trip to Italy, they brought the game to Rome in the hopes of restarting the sport, as in the original timeline Italians were hardcore soccer enthusiasts.