Barring a problem with technical issues, baseball will introduce instant replay around Sept. 1, a source told Sporting News on Thursday morning.

Replay discussions involving the commissioner's office, the players' association and umpires union have been taking place for weeks. All sides appear to be in agreement about how replay will be used - only on home run boundary calls -- and how it will be implemented.

There will be a so-called war room in New York where a technician will provide video feeds to monitors set up for umpires at all 30 parks.

The commissioner's office is not expected to announce an official start date until the technology is working at all 30 stadiums. The technology has been tested at some parks but is not in place at every park, according to a source.

The commissioner's office already has pushed back the start date from Aug. 1 to Aug. 15, with Sept. 1 now the latest target date.

Other details also are still being finalized, including who will watch the replays - all four umpires, or the crew chief only. The crew chief is expected to have the final say.

Major league ballparks are being wired for instant replay, and commissioner Bud Selig said Thursday his "confidence is growing" that the technology to assist umpires will be ready soon.

"I want to make sure that if and when we do it, it's really good, it's perfect," Selig said at the conclusion of a two-day owners' meeting. "It'll be very limited. I want to make sure, and I'm not quite certain yet. But we should have answers very shortly."

Selig said he has visited the so-called "war room" in New York where officials would review video feeds of disputed home runs. The NHL has a similar setup in Toronto.

"We've spent a lot of time doing a lot of wiring of ballparks, doing a lot of checking," Selig said. "Let's just say my confidence is growing."

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Negotiations have been ongoing with the players' association and the umpires' union, and the use of replays could start this month.

Selig was once a staunch opponent of replay, but a spate of missed home run calls this season has changed his stance.

Replays would be used to only determine whether a ball leaving the field is fair or foul, or whether it actually went over the fence. It would not be used on close plays on the bases or balls and strikes.

Replay was discussed at the meetings but doesn't require a vote among the owners because it is not a rule change.