A new instant replay system will be implemented for Japan's professional baseball from next season. The Mainichi Shimbun answers some common questions readers may have about the new framework.

Question: What is the new review system in professional baseball starting next season?

Answer: It's called the "request" system. When a manager is not happy with a ruling that an umpire gives for plays happening at any of the bases during a game, they can request a video replay to umpires. The existing video replay system introduced in 2010 limits what can be reviewed, such as whether the hit was a home run, and is used only when umpires judge that a video review is necessary.

Q: How does a manager use their "request" card?

A: The manager comes out of the dugout and sends an umpire a signal. The umpires check the video replay and must come up with a conclusion within five minutes. A manager can exercise their right to request a review up to two times in the nine innings of a regular game and one time during extra innings. If the initial ruling was overturned as a result of a video replay, the number of times they can request a review does not get reduced. However, a manager cannot request a review when it comes to judgments for pitches such as calling a strike or a ball, as well as a balk.

Q: Why is the new system being implemented?

A: Nippon Professional Baseball (NPB) is aiming to achieve fair rulings that will make managers, players and fans happy. In 2014, Major League Baseball started the "challenge" system in which managers can request a video review of a play. Unlike the American organization that uses expensive machines specialized for video replays, Japan's NPB will utilize images broadcasted on TV. NPB has decided to call it a "request" system rather than "challenge" out of respect for the umpires.

Q: Will the new system help umpires?

A: If every play was to get reviewed, it would disrupt the smooth progress of the game. The role of video replays is merely supplementary. It does not change the fact that the skills of umpires who call quick decisions for a play that happens in a flash are still the core of a good ball game. (Answers by Takumi Hosoya, Sports News Department)