CHICAGO -- Theo Epstein didn't waste any time getting his band back together.

The Cubs announced Wednesday night that Jed Hoyer and Jason McLeod will leave the Padres front office to join Epstein's baseball operations department in Chicago, effective immediately. The Cubs have agreed to send the Padres a player to be named as compensation.

Hoyer, who was the Padres' general manager, takes over as the Cubs' GM, while McLeod will be the head of scouting and player development. Current Cubs player development director Oneri Fleita, who was given a four-year contract extension, and scouting director Tim Wilken will report to McLeod.

Major League Baseball waived its blackout on Tuesday to allow the Cubs to hold a news conference and introduce Epstein as the new president of baseball operations. Because of Wednesday's postponement of Game 6, MLB gave the Cubs and Padres the go-ahead to announce Hoyer and McLeod's new jobs.

Both the Cubs and the Padres intend to hold news conferences after the World Series. At that time, the Padres intend to announce Josh Byrnes as Hoyer's successor as general manager.

The Cubs made the announcement less than 48 hours after Epstein was introduced.

"If we bring in someone as a general manager," Epstein said Tuesday during his news conference, "it will be because there's someone who I think is one of the best and one of the brightest in the game and someone who can make a real impact or the Cubs. We have a ton of work to do."

Epstein, Hoyer and McLeod combined in Boston to put together two World Series championship teams in 2004 and '07. Hoyer rose from a baseball operations intern in 2002 with the Red Sox to an assistant the next year.

"The only way [to win consistently] is through scouting and player development," Hoyer said when hired in San Diego. "I want to build it from within. There's no magic formula that I learned in Boston, no 'special sauce.' It comes down to the building blocks of baseball, which are scouting and development."

Hoyer was named the eighth GM in Padres history in October 2009, and in his first season, the team won 90 games for the fourth time in franchise history. He had spent eight years in Boston where he worked as an assistant general manager with Epstein. He first joined the Red Sox in 2002 and was actively involved in player development, Major League scouting, quantitative analysis and advance scouting.

He also served as co-general manager in Boston in a 44-day stint when Epstein briefly left the Red Sox. In that short period, he completed a seven-player trade for Josh Beckett and Mike Lowell in which Hanley Ramirez, Anibal Sanchez and two other Minor Leaguers went to the Marlins. Beckett and Lowell were named ALCS MVP and World Series MVP in 2007, respectively.

Hoyer pitched and was a shortstop for Wesleyan University, and helped lead the Cardinals to the championship game of the NCAA Division III World Series in 1994. He still holds the school record for career saves.

Now, he is the Cubs' 14th general manager, taking over for Jim Hendry, who was dismissed in August. Randy Bush had been Chicago's interim general manager, and the Cubs have yet to announce what his role will be in the revamped front office.

McLeod rejoined the Padres in 2009 as assistant general manager, overseeing amateur scouting and player development. He had worked for the Red Sox and Epstein for six years, joining Boston in '03. His first Draft with the Red Sox produced 2007 AL Rookie of the Year and 2008 AL MVP Dustin Pedroia.

Baseball America ranked the Red Sox's Draft among the top five in three of his first four years in Boston. Other players selected under McLeod included Jacoby Ellsbury, Jed Lowrie, Daniel Bard and Clay Buchholz.

The Cubs' farm system has produced players such as Starlin Castro, Geovany Soto, Andrew Cashner, Darwin Barney, Carlos Marmol and James Russell. But Wilken took a more aggressive tack this past June, with the blessing of owner Tom Ricketts, rather than the conservative approach the Cubs had taken in the past. The players signed, including Javier Baez, Shawon Dunston Jr., Dan Vogelbach, Dillon Maples, Trevor Gretzky and Taiwan Easterling, were expensive and high risk.

"As the Cubs' Draft went on, we were sitting in our Draft room, and we could tell what they were doing," Epstein said on Tuesday. "We said, 'Hey, they get it, they're finally getting it.' ... That got my attention, the attention of a lot of people in the game. I would say it was a significant moment."

Now, they'll get a boost from McLeod. The great grand nephew of Hall of Fame pitcher Carl Hubbell, McLeod pitched in the Minors from 1991-92 before taking his first internship with the Padres.