Starting tomorrow, Major League Baseball will use instant replay to rule on disputed home runs.

The decision, which had been expected for weeks, was announced by commissioner Bud Selig yesterday. The Phillies support the plan.

"I think it's the right thing to do," assistant general manager Ruben Amaro said. "I know it's difficult to implement in the middle of a season, but the games are important in September. I hope it works well."

The Phillies were one of 25 clubs - five teams opposed it - to vote in favor of using replay on disputed home-run calls at the general managers' meetings in November.

The results of that vote, coupled with advances in technology, persuaded Selig, formerly an opponent of replay, to support its being used to decide disputed home runs. The move was approved by the players' association and umpires' union, though Tim McClelland, the umpire crew chief for last night's Mets-Phillies game at Citizens Bank Park, declined comment. Through an intermediary, McClelland said his union asked that he not comment.

Replay will not be used for calls on the bases or other judgment calls. It will be used only to determine whether a potential home-run ball cleared the outfield wall, whether it was fair of foul, or whether a fan interfered. By using replay for the final month of the regular season, baseball has a chance to work out kinks before the postseason.

Video will be reviewed in New York by a technician and an umpire supervisor. The crew chief at the stadium will view the replay and make the final call, overturning the call on the field only if he sees clear and convincing evidence. Anyone leaving the dugout to argue a call after it has been reviewed will be ejected.

The Phillies have long been in favor of using instant replay on disputed home runs. Their desire for it was fueled on Sept. 26, 2006 when, in the heat of a playoff race, they suffered a crushing 4-3 loss at Washington's RFK Stadium.

In the second inning of that game, with two men on base, Chase Utley hit a ball off the right-field foul pole. Without the benefit of replay, umpires ruled the ball foul, denying the Phils a chance to take 5-1 lead.

"We play all year long, and we're trying to get somewhere, and all we need is for somebody to miss a call like that," manager Charlie Manuel said after that game. "It's terrible. It's absolutely unreal."

Four days after that loss, the Phils were eliminated from wild-card contention.

"What people don't understand is how it affects you," Manuel said yesterday. "We had a chance to win the wild card. That [blown call] helped bury us. It's a tough way to get eliminated. But at the same time, some calls have gone our way."

"I don't think it's bad," first baseman Ryan Howard said. "It's all about getting the call right. That's what everyone wants."