"We made a gigantic move today and I'm very pleased about that," Commissioner Bud Selig said at the meeting of general managers and owners where the announcement was made.
Owners must give their final approval in January for the new replay system to become operative next season. The associations representing players and umpires also must approve the plan.
The replay system would allow every on-field action to be subject to review except balls and strikes and whether a batter checks his swing.
A replay would be put in use by a manager's challenge. Each manager would be allowed unlimited challenges as long as those challenges continue to successfully overturn an umpire's call.
Once a manager has made two unsuccessful challenges, he would not be allowed to make any more.
A limited replay system has been in use since 2008 to determine whether a potential home run was fair or foul and whether a fan interfered with a play.
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