The Assn. of Tennis Professionals changed a...

The Assn. of Tennis Professionals changed a rule in hopes of eradicating temper tantrums on court, abusive tirades at officials and long delays in play.

Instead of the current four-step penalty system--warning, point, game, default--ATP events will have a three-step system--warning, point, default.

The ATP, which takes over the men’s tour in 1990, also announced that it will expand drug tests by adding steroids and other possible performance-enhancing substances to the list of current detectables, will begin a new ranking system and will make changes to speed up play while allowing a break between all sets.