No date has been set for when Andy MacPhail will officially take over for Pat Gillick as Phillies president. The passing of the baton, as MacPhail referred to it Thursday, will occur when Gillick is ready, MacPhail said.

Gillick said minutes later he will hand off to MacPhail probably in the next "45 days or so," which means the official change should happen, at latest, just before the annual organizational meetings, which begin Oct. 26 in Clearwater, Fla.

But regardless of when the formal transfer of power occurs, the Andy MacPhail era of Phillies baseball, for all intents and purposes, began Thursday at 12:14 p.m., when the team announced via a news release that it would not renew the contract of oft-maligned general manager Ruben Amaro Jr.

The decision, while not unexpected, set the stage for an intriguing six weeks during which MacPhail's GM search will be the biggest story line surrounding this rebuilding team. Six weeks, of course, presumes MacPhail gets his No. 2 in place before the organizational meetings, a time line he called "ambitious but ideal."

The name you will hear most in the coming weeks is Matt Klentak, the 34-year-old assistant general manager of the Los Angeles Angels. Klentak was MacPhail's protege with the Baltimore Orioles, where MacPhail hired the then- 27-year-old to be his director of baseball operations before the 2007 season.

Klentak spent four years before that working in labor relations for Major League Baseball, where he first worked with MacPhail on the collective bargaining team during the 2006 labor negotiations. Klentak hails from the Northeast - Medfield, Mass., a Boston suburb - and is a 2002 graduate of Dartmouth College, where he started for three years at shortstop and earned a degree in economics.

Although he has yet to lead a baseball operations department, Klentak, who reportedly interviewed for the Angels' GM opening, is an up-and-comer whom MacPhail could groom as his top lieutenant. John Middleton, the influential Phillies co-owner, said Thursday that he wanted MacPhail to "hire himself." Who better fits that description than MacPhail's former apprentice?

But ultimately, this early in the process, no one aside from MacPhail - and perhaps ownership - truly knows which candidates MacPhail is considering. With his vast experience leading the Minnesota Twins, Chicago Cubs, and Orioles, MacPhail, 62, has a wide network of contacts around the game from which to draw.

Several of the potential candidates, like Klentak, could have previous ties to the highly respected MacPhail.

Wayne Krivsky, the 61-year-old former Cincinnati Reds GM, was a special assistant to MacPhail for the 2009 season in Baltimore. In 2011, after a stint with the New York Mets, Krivsky was hired by the Twins as a special assistant to GM Terry Ryan, who in 1994 succeeded MacPhail as Minnesota's GM. John Barr, the San Francisco Giants assistant GM who hails from Audubon, N.J., was the East Coast supervisor for the MacPhail-led Twins in 1988.

But that doesn't mean that having a MacPhail connection is a prerequisite for landing the job.

J.J. Picollo, a 44-year-old Cherry Hill native, is highly speculated about as a candidate, given the success of the Kansas City Royals, where he is the assistant GM in charge of player personnel. Billy Eppler, a 39-year-old assistant GM with the New York Yankees, is a name that seemingly always comes up when GM jobs open.

Countless other executives could fit into the "wide spectrum" of candidates MacPhail intends to explore. If he seeks a more analytically minded GM, Matt Arnold, the Tampa Bay Rays' pro scouting director, fits the mold, as would the likes of Klentak and Miami Marlins director of pro scouting Jeff McAvoy, who previously worked for the Rays and Houston Astros.

During Thursday's news conference, MacPhail did not offer many hints about which type of GM he seeks. He did provide this criterion, though:

"I think one thing is they need to have a little different horizon than the manager does," he said. "If your general manager is just focused on tomorrow's game or next week or what happens in the sixth inning of tonight's game, then you have two people doing the same job, because that's what the manager's doing.

"The GM has always got to have a horizon that's just a little bit wider. . . . The consequences of what we do today, what impact is that going to have in a variety of different ways, two or three years down the road?"

At this point, amid the first days of MacPhail's search, the Phillies' next GM could be any number of candidates.

Of much more certainty is that the MacPhail era - officially or not - is underway.

@jakemkaplan