As a principle, play should be continuous, from the time the match starts (when the first service of the match is put in play) until the match finishes.
Between points, a maximum of twenty (20) seconds is allowed. When the players change ends at the end of a game, a maximum of ninety (90) seconds are allowed. However, after the first game of each set and during a tie-break game, play shall be continuous and the players shall change ends without a rest.
At the end of each set there shall be a set break of a maximum of one hundred and twenty (120) seconds.
The maximum time starts from the moment that one point finishes until the first service is struck for the next point.
USTA Comment 29.1: The 20-second time limit does not apply if a player has to chase a stray ball.