COOPERSTOWN, N.Y. -- After Tony La Russa briefly came out of retirement to manage the victorious National League squad in the 2012 All-Star Game, he said he had been assigned by Commissioner Bud Selig to a top-secret project.

Asked what that project might be, the former Cardinals skipper and future Hall of Famer smiled slyly.

"If I told you, I'd have to kill you," La Russa said.

Now we know. For the past year, La Russa -- with the help of fellow former manager Joe Torre and Braves president John Schuerholz -- has been charged with helping to expand instant replay in Major League Baseball.

If the owners cast votes of approval in November and the unions for the players and umpires do the same, baseball will implement the first phase of an instant replay challenge system controlled by the managers next season.

"It's the first time in baseball history that managers have been empowered with this capability," Schuerholz told the media after presenting the plan at the Owners Meetings on Thursday morning. "You should also know that the umpires are very, very receptive to this. They have spent enough time being abused, being the butt of bad comments. They understand that the technology can be a valuable tool for them."

This is a very good thing.

"You can see in the past 20, 25 years the sport has changed, and I think for the better," Selig said. "This is something we did very carefully ... in my usual slow process. John Schuerholz and I have been friends for many years, and, of course, Joe and Tony have been remarkable. I knew it was in good hands. They kept me very well abreast of things. So, during the presentation today, I couldn't help but sense the acceptance and excitement in the room."

MLB began utilizing instant replay on a limited basis on Sept. 3, 2008, when review of home runs -- fair or foul, in or out of the ballpark -- was allowed by discretion of the umpires. The fate of the western world didn't change with that implementation.

Given that a single missed call in a big game could mean the difference between a team making or missing the playoffs, or even winning a World Series title, the expansion of replay has received its share of support, even from general managers.

When Torre retired from managing at the end of the 2010 season, he was hired by Selig as MLB's executive vice president of baseball operations. A year prior to that, Torre, Schuerholz, La Russa, Angels manager Mike Scioscia and Tigers skipper Jim Leyland were named to Selig's special committee charged with recommending on-field changes.

In Torre -- another certain Hall of Famer who has had Selig's admiration, respect and ear -- the GMs wound up having a stout ally regarding the expanded use of instant replay.

At first blush, the committee recommended that replay be used to review trapped balls in the outfield and drives hit fair or foul down the lines. The Players Association agreed, and that rule was memorialized in the current Basic Agreement that was signed in late 2011.

Under the latest proposal, 89 percent of all questionable plays can be challenged by managers -- one challenge coming during the first six innings and two more from the seventh inning until the end of the game. The manager retains the challenge if the play is overturned but loses it if it isn't.

The review won't be handled by the umpires on the field, but by a crew of officials at MLB Advanced Media's headquarters in New York. The decision of the officials in New York will stand, Schuerholz said.

At the moment, the state of the plays that can be argued but not reviewed -- 11 percent of past incorrect calls -- is still evolving.

"Most of those plays, if they are turned over, the reset of the runners and the reset of the play would be mind boggling," Schuerholz added. "So that's the way we've chosen to start."

The entire system will remain under review and be adjusted in three phases during the course of its first three years. It will be tested this October in the Arizona Fall League. At the same time, managers and umpires will be trained in its nuances, beginning in Orlando, Fla., at the Winter Meetings and during Spring Training.

"I think managers will learn to judiciously utilize their challenges," Schuerholz said. "The data we have is that there is only one missed call every five games. So if you have three challenges, you should be able to cover those events that you believe are critical to the outcome of your game."