Umpires will be equipped with microphones to inform crowds in the ballparks and the viewing audience at home of instant replay reviews, Major League Baseball announced Friday.

Beginning with exhibition games this weekend, crew chiefs will wear a microphone to announce when a play is being challenged and what is being challenged and reviewed. When a team issues a challenge, the umpire will proceed to either baseline and face the press box to make the announcement, prior to communicating with the replay official in New York.

After reviews are completed, the crew chief will return to the same spot to make a post-review announcement of the ruling and any changes to the placement of runners.

This system, which will be similar to the one used by NFL officials, will also be used when a crew chief review is initiated without a prompt from either dugout (typically, on potential home run reviews). In those instances, the crew chief will also jog to the baseline to make the announcement.

The procedure by which managers request reviews will go unchanged. A manager has a 20-second time period to alert the umpire (by verbal communication or hand signal) whether he wishes to issue a challenge, and the challenge may not be rescinded once it has been exercised.