Major League Baseball moved one step closer to implementing instant replay on Wednesday after an agreement was signed by the umpires and league management.

“We reached an agreement. Final decision with respect to moving ahead has not been made yet, but we have an agreement with the umpires,” said Rob Manfred, baseball’s executive vice president of labor relations.

The agreement states that replays will be limited to boundary calls, such as determining whether fly balls were fair or foul, or whether they went over fences. Umpire crew chiefs will determine when instant replay is to be utilized and will make the final decision on calls.

Up to three umpires will be able to review the replay, which will be provided in a war room of sorts at MLB Advanced Media in New York City. It’s possible that during the postseason as many as five umpires could review a play.

“We’re going to move forward with the understanding the sides will come to the table later and iron out some of the remaining issues,” said World Umpires Association spokesman Lamell McMorris, who criticized management on Tuesday. “Instant replay will be a work in progress.”

There will be some sort of formal training for all umpires, not just crew chiefs.

The agreement comes hours after the WUA had decided to boycott a conference call in which crew chiefs were to go over instant replay with MLB officials. The call was subsequently cancelled by MLB.

MLB continues to discuss the issue with the Players Association, although they continue to maintain the position that they are not legally obligated to do so.

“We’re still in discussions with them,” players’ association general counsel Michael Weiner said.