Tiebreak (tennis)

The tennis scoring system is the standard system by which tennis matches and tournaments are generally operated and scored.

A tennis tournament is organized into matches between players (for singles tournaments) or teams of two players (for doubles tournaments). Very often the tournament takes the form of a knockout tournament consisting of several rounds. In round 1, all players (or teams) are paired (assuming there are no byes) and play a match against each other. The losers are eliminated, and take no further part in the tournament (this is single elimination). The winners are again paired to matches in the next round. The tournament continues until the quarterfinal round (having eight players or teams playing a total of four matches), then the semifinal round (four players or teams, two matches), and finally the final round (with just two players or teams) is played. The winner of the final round is declared the winner of the entire tournament.

A tennis match is composed of points, games, and sets. A set consists of a number of "games" (a minimum of six), which in turn each consist of points.

A set is won by the first side to win 6 games, with a margin of at least 2 games over the other side (e.g. 6-3 or 7-5). There is usually a tie-break if the set is tied at six games per player.

A match is won when a player or a doubles team wins the majority of prescribed sets. Matches are either a best of three sets or best of five sets format. The best of five set format is typically only played in the men's singles or doubles matches at Majors and Davis Cup matches.

The sides serve alternately, and often the server has an advantage over the non-server. It is only possible to win a set by breaking the opponent's service game at least once, before a tiebreak is required. Likewise, it is not possible to win a tiebreak without winning at least one point during an opponent's turn at serve (called a mini-break).

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