The phrase "one's superior goal difference" refers to a team or individual's advantage in terms of goals scored compared to their opponents. In sports like soccer, basketball and football, teams compete against each other with the aim of scoring more goals than their opponent. The term 'goal difference' is calculated by subtracting the number of goals conceded from the number of goals scored. If a team has a positive goal difference, it means they have scored more goals than they have conceded and if negative, then they have conceded more goals than they have scored. A superior goal difference implies that a team has achieved a significant advantage in terms of scoring over their opponents which can be crucial in determining the outcome of a match or tournament.