As an expert in the field of tennis, I can provide a comprehensive understanding of the scoring system and the terminology used when the score reaches 40-40.

Tennis is a sport with a unique scoring system that can be quite intricate for those not familiar with it. The scoring in tennis is based on a system of points, games, and sets. A point is the most basic unit of scoring, and a game is won by the player who first scores four points with a margin of at least two points over the opponent. A set is won when a player or team wins at least six games with a margin of two games over their opponent.

When the score in a game reaches 40-40, it is referred to as a deuce. The term "deuce" is derived from the French word "deux," which means two, indicating that both players have an equal number of points. At this stage, one player must win two consecutive points to win the game. If a player wins the next point after deuce, the score is called advantage for that player. The term "advantage" signifies that the player is one point away from winning the game. If the opponent wins the next point, the score returns to deuce, and they continue to play until one player has a two-point lead.

The reference to serving from the left side at deuce and the term "ad-court" is related to the traditional scoring system known as "Ad-Scoring." In Ad-Scoring, after a deuce, the server switches sides and serves from the ad-court, which is the left side of the court when facing the net. This is because the next point, if won by the server, would be an advantage point, and advantage points are always played from the ad-court. The term "ad" is short for "ace," which is a term used when a server wins a point without the opponent touching the ball.

However, the reference to "No-Ad-Scoring" indicates a different scoring system that has been implemented in some tennis tournaments and matches. Under the No-Ad-Scoring rules, the traditional "advantage" scoring is eliminated. Instead, once a score of deuce (40-40) is reached, the next point won by a player is considered the point that wins the game. This system simplifies the scoring and speeds up the game.

In summary, when the score is 40-40 in tennis, it is called a deuce. From deuce, a player must win two points in a row to win the game. In traditional scoring, serving from the left side is to the ad-court, and the next point after deuce is an advantage point. In No-Ad-Scoring, the game is decided by the next point won after deuce.

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This is of course because whenever the score is deuce you serve from this side. If you serve from the left side it is called serving from the ad-court because advantage points are played on this side! No-Ad-Scoring. With no-ad scoring rules, the game is decided once deuce or 40-40 is reached.read more >>